# CRC-32

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
CRC-32
You are encouraged to solve this task according to the task description, using any language you may know.

Demonstrate a method of deriving the Cyclic Redundancy Check from within the language.

The result should be in accordance with ISO 3309, ITU-T V.42, Gzip and PNG.

Algorithms are described on Computation of CRC in Wikipedia. This variant of CRC-32 uses LSB-first order, sets the initial CRC to FFFFFFFF16, and complements the final CRC.

For the purpose of this task, generate a CRC-32 checksum for the ASCII encoded string:

`The quick brown fox jumps over the lazy dog`

## 11l

Translation of: C
```V crc_table = [0] * 256
L(i) 256
UInt32 rem = i
L 8
I rem [&] 1 != 0
rem >>= 1
rem (+)= EDB8'8320
E
rem >>= 1
crc_table[i] = rem

F crc32(buf, =crc = UInt32(0))
crc = (-)crc
L(k) buf
crc = (crc >> 8) (+) :crc_table[(crc [&] F'F) (+) k.code]
R (-)crc

print(hex(crc32(‘The quick brown fox jumps over the lazy dog’)))```
Output:
```414FA339
```

## 6502 Assembly

```PRHEX	EQU  \$FDDA ; <= REPLACE THIS WITH THE PRHEX ROUTINE FOR YOUR MACHINE

string	EQU  \$EC
length	EQU  \$EE
crc0	EQU  \$FA
crc1	EQU  \$FB
crc2	EQU  \$FC
crc3	EQU  \$FD
table0	EQU  \$9200
table1	EQU  \$9300
table2	EQU  \$9400
table3	EQU  \$9500
ORG  \$9114
LDA #<text
STA  string
LDA #>text
STA  string+1
LDA #\$2b ; length of text
STA  length
LDA #\$00
STA  length+1
STA  crc0
STA  crc1
STA  crc2
STA  crc3
JSR  crc32
LDA  crc3
JSR  PRHEX
LDA  crc2
JSR  PRHEX
LDA  crc1
JSR  PRHEX
LDA  crc0
JMP  PRHEX
text
ASC 'The quick brown fox jumps over the lazy dog'
; ORG  \$916E
crc32
JSR  start
LDY  string
STX  string
loop
LDA length
BNE no_borrow
LDA length+1
BEQ ones_complement
DEC length+1
no_borrow
DEC length
LDA (string),Y
EOR  crc0
TAX
LDA  table0,X
EOR  crc1
STA  crc0
LDA  table1,X
EOR  crc2
STA  crc1
LDA  table2,X
EOR  crc3
STA  crc2
LDA  table3,X
STA  crc3
INY
BNE  loop
INC  string+1
BNE  loop
start
have_table
LDX #\$00
BNE  loop4 ; LDX #\$04 BNE ones_complement
loop256
LDA #\$00
STA  table3,X
STA  table2,X
STA  table1,X
TXA
STA  table0,X
LDY #\$08
loop8
LSR  table3,X
ROR  table2,X
ROR  table1,X
ROR  table0,X
BCC  no_xor
LDA  table3,X
EOR #\$ED
STA  table3,X
LDA  table2,X
EOR #\$B8
STA  table2,X
LDA  table1,X
EOR #\$83
STA  table1,X
LDA  table0,X
EOR #\$20
STA  table0,X
no_xor
DEY
BNE  loop8
INX
BNE  loop256
ones_complement
LDX #\$04
STX  have_table+1 ; self-modify
loop4
DEX
LDA  crc0,X
EOR #\$FF
STA  crc0,X
TXA
BNE loop4
RTS```

Works with: GNAT
```with Ada.Text_IO; use Ada.Text_IO;
with GNAT.CRC32; use GNAT.CRC32;
with Interfaces; use Interfaces;
procedure TestCRC is
package IIO is new Ada.Text_IO.Modular_IO (Unsigned_32);
crc : CRC32;
num : Unsigned_32;
str : String := "The quick brown fox jumps over the lazy dog";
begin
Initialize (crc);
Update (crc, str);
num := Get_Value (crc);
IIO.Put (num, Base => 16); New_Line;
end TestCRC;
```
Output:
`16#414FA339#`

## Arturo

```print crc "The quick brown fox jumps over the lazy dog"
```
Output:
`414FA339`

## ALGOL 68

```[0:255]BITS crc_table;
BOOL crc_table_computed := FALSE;

PROC make_crc_table = VOID:
BEGIN
INT n, k;
FOR n FROM 0 TO 255 DO
BITS c := BIN n;
FOR k TO 8 DO
c := IF 32 ELEM c THEN
16redb88320 XOR (c SHR 1)
ELSE
c SHR 1
FI
OD;
crc_table[n] := c
OD;
crc_table_computed := TRUE
END;

PROC update_crc = (BITS crc, STRING buf) BITS:
BEGIN
BITS c := crc XOR 16rffffffff;
INT n;

IF NOT crc_table_computed THEN make_crc_table FI;
FOR n TO UPB buf DO
c := crc_table[ABS ((c XOR BIN ABS buf[n]) AND 16rff)] XOR (c SHR 8)
OD ;
c XOR 16rffffffff
END;

PROC hex = (BITS x) STRING :
BEGIN
PROC hexdig = (BITS x) CHAR: REPR (IF ABS x ≤ 9 THEN ABS x + ABS "0"
ELSE ABS x - 10 + ABS "a"
FI);
STRING h := "";
IF x = 16r0 THEN
h := "0"
ELSE
BITS n := x;
WHILE h := hexdig (n AND 16rf) + h; n ≠ 16r0 DO
n := n SHR 4
OD
FI;
h
END;

PROC crc = (STRING buf) BITS:
update_crc(16r0, buf);

STRING s = "The quick brown fox jumps over the lazy dog";
print(("CRC32 OF ", s, " is: ", hex (crc (s)), newline))```
Output:
`CRC32 OF The quick brown fox jumps over the lazy dog is: 0414fa339`

## Applesoft BASIC

### Implementation using Binary ASCII

``` 0 DIM D\$(1111):D\$(0)="0":D\$(1)="1":D\$(10)="2":D\$(11)="3":D\$(100)="4":D\$(101)="5":D\$(110)="6":D\$(111)="7":D\$(1000)="8":D\$(1001)="9":D\$(1010)="A":D\$(1011)="B":D\$(1100)="C":D\$(1101)="D":D\$(1110)="E":D\$(1111)="F"
1 Z\$ =  CHR\$ (8) +  CHR\$ (8) +  CHR\$ (8) +  CHR\$ (8) +  CHR\$ (8) +  CHR\$ (8) +  CHR\$ (8) +  CHR\$ (8) +  CHR\$ (8) +  CHR\$ (8)
100 C\$ = "00000000000000000000000000000000"
110 S\$ = "The quick brown fox jumps over the lazy dog"
120  GOSUB 200"CRC32
130  PRINT D\$( VAL ( MID\$ (C\$,1,4)))D\$( VAL ( MID\$ (C\$,5,4)))D\$( VAL ( MID\$ (C\$,9,4)))D\$( VAL ( MID\$ (C\$,13,4)))D\$( VAL ( MID\$ (C\$,17,4)))D\$( VAL ( MID\$ (C\$,21,4)))D\$( VAL ( MID\$ (C\$,25,4)))D\$( VAL ( MID\$ (C\$,29,4)))"  ";
140  END
200  IF  LEN (S\$) = 0 THEN  RETURN
210  GOSUB 280"XOR #\$FFFFFFFF
220  FOR I = 1 TO  LEN (S\$)
230 R\$ = "00000000" +  MID\$ (C\$,1,24)
235  PRINT D\$( VAL ( MID\$ (C\$,1,4)))D\$( VAL ( MID\$ (C\$,5,4)))D\$( VAL ( MID\$ (C\$,9,4)))D\$( VAL ( MID\$ (C\$,13,4)));
236  PRINT D\$( VAL ( MID\$ (C\$,17,4)))D\$( VAL ( MID\$ (C\$,21,4)))D\$( VAL ( MID\$ (C\$,25,4)))D\$( VAL ( MID\$ (C\$,29,4)))" " MID\$ (S\$,I,1)Z\$;
240 C =  ASC ( MID\$ (S\$,I,1)):O\$ = "": FOR B = 1 TO 8:K =  INT (C / 2):O\$ =  STR\$ (C - K * 2) + O\$:C = K: NEXT B
250 A = ( MID\$ (C\$,25,1) <  >  MID\$ (O\$,1,1)) * 128 + ( MID\$ (C\$,26,1) <  >  MID\$ (O\$,2,1)) * 64 + ( MID\$ (C\$,27,1) <  >  MID\$ (O\$,3,1)) * 32 + ( MID\$ (C\$,28,1) <  >  MID\$ (O\$,4,1)) * 16
251 A = ( MID\$ (C\$,29,1) <  >  MID\$ (O\$,5,1)) * 8 + ( MID\$ (C\$,30,1) <  >  MID\$ (O\$,6,1)) * 4 + ( MID\$ (C\$,31,1) <  >  MID\$ (O\$,7,1)) * 2 + ( MID\$ (C\$,32,1) <  >  MID\$ (O\$,8,1)) + A: GOSUB 300
260 C\$ =  STR\$ (( MID\$ (R\$,1,1) <  >  MID\$ (T\$,1,1))) +  STR\$ (( MID\$ (R\$,2,1) <  >  MID\$ (T\$,2,1))) +  STR\$ (( MID\$ (R\$,3,1) <  >  MID\$ (T\$,3,1))) +  STR\$ (( MID\$ (R\$,4,1) <  >  MID\$ (T\$,4,1)))
261 C\$ = C\$ +  STR\$ (( MID\$ (R\$,5,1) <  >  MID\$ (T\$,5,1))) +  STR\$ (( MID\$ (R\$,6,1) <  >  MID\$ (T\$,6,1))) +  STR\$ (( MID\$ (R\$,7,1) <  >  MID\$ (T\$,7,1))) +  STR\$ (( MID\$ (R\$,8,1) <  >  MID\$ (T\$,8,1)))
262 C\$ = C\$ +  STR\$ (( MID\$ (R\$,9,1) <  >  MID\$ (T\$,9,1))) +  STR\$ (( MID\$ (R\$,10,1) <  >  MID\$ (T\$,10,1))) +  STR\$ (( MID\$ (R\$,11,1) <  >  MID\$ (T\$,11,1))) +  STR\$ (( MID\$ (R\$,12,1) <  >  MID\$ (T\$,12,1)))
263 C\$ = C\$ +  STR\$ (( MID\$ (R\$,13,1) <  >  MID\$ (T\$,13,1))) +  STR\$ (( MID\$ (R\$,14,1) <  >  MID\$ (T\$,14,1))) +  STR\$ (( MID\$ (R\$,15,1) <  >  MID\$ (T\$,15,1))) +  STR\$ (( MID\$ (R\$,16,1) <  >  MID\$ (T\$,16,1)))
264 C\$ = C\$ +  STR\$ (( MID\$ (R\$,17,1) <  >  MID\$ (T\$,17,1))) +  STR\$ (( MID\$ (R\$,18,1) <  >  MID\$ (T\$,18,1))) +  STR\$ (( MID\$ (R\$,19,1) <  >  MID\$ (T\$,19,1))) +  STR\$ (( MID\$ (R\$,20,1) <  >  MID\$ (T\$,20,1)))
265 C\$ = C\$ +  STR\$ (( MID\$ (R\$,21,1) <  >  MID\$ (T\$,21,1))) +  STR\$ (( MID\$ (R\$,22,1) <  >  MID\$ (T\$,22,1))) +  STR\$ (( MID\$ (R\$,23,1) <  >  MID\$ (T\$,23,1))) +  STR\$ (( MID\$ (R\$,24,1) <  >  MID\$ (T\$,24,1)))
266 C\$ = C\$ +  STR\$ (( MID\$ (R\$,25,1) <  >  MID\$ (T\$,25,1))) +  STR\$ (( MID\$ (R\$,26,1) <  >  MID\$ (T\$,26,1))) +  STR\$ (( MID\$ (R\$,27,1) <  >  MID\$ (T\$,27,1))) +  STR\$ (( MID\$ (R\$,28,1) <  >  MID\$ (T\$,28,1)))
267 C\$ = C\$ +  STR\$ (( MID\$ (R\$,29,1) <  >  MID\$ (T\$,29,1))) +  STR\$ (( MID\$ (R\$,30,1) <  >  MID\$ (T\$,30,1))) +  STR\$ (( MID\$ (R\$,31,1) <  >  MID\$ (T\$,31,1))) +  STR\$ (( MID\$ (R\$,32,1) <  >  MID\$ (T\$,32,1)))
270  NEXT I
280 B\$ = "": FOR B = 1 TO 32:B\$ = B\$ +  STR\$ (( MID\$ (C\$,B,1) <  > "1")): NEXT B:C\$ = B\$
290  RETURN
300  IF  NOT T THEN  DIM T\$(255): FOR T = 0 TO 38: READ J: READ T\$(J): NEXT T
310  IF  LEN (T\$(A)) THEN T\$ = T\$(A): RETURN
320 R = A:T\$ = "": FOR B = 1 TO 8:N =  INT (R / 2):T\$ =  MID\$ ("01",R - N * 2 + 1,1) + T\$:R = N: NEXT B:T\$ = "000000000000000000000000" + T\$
330  FOR J = 0 TO 7
340 X =  VAL ( MID\$ (T\$,32,1))
350 T\$ = "0" +  MID\$ (T\$,1,31)
360  IF X THEN B\$ = "": FOR B = 1 TO 32:B\$ = B\$ +  MID\$ ("01",( MID\$ (T\$,B,1) <  >  MID\$ ("11101101101110001000001100100000",B,1)) + 1,1): NEXT B:T\$ = B\$
370  NEXT J
380 T\$(A) = T\$:T = T + 1
390  RETURN
600  DATA171,01000001000001000111101001100000
610  DATA247,00100011110110010110011110111111
620  DATA95,11111011110101000100110001100101
630  DATA217,11111111000011110110101001110000
640  DATA213,11110110101110010010011001011011
650  DATA179,01010010011010001110001000110110
660  DATA141,10010011000010011111111110011101
670  DATA90,10001011101111101011100011101010
680  DATA224,10100000000010101110001001111000
690  DATA187,01011100101100110110101000000100
700  DATA169,10101111000010100001101101001100
710  DATA60,00101111011011110111110010000111
720  DATA128,11101101101110001000001100100000
730  DATA36,00111100000000111110010011010001
740  DATA235,00110111110110000011101111110000
750  DATA229,11010000011000000001011011110111
760  DATA77,00001000011011010011110100101101
770  DATA167,01001000101100100011011001001011
780  DATA1,01110111000001110011000010010110
790  DATA119,11001110011000011110010010011111
800  DATA96,01001101101100100110000101011000
810  DATA158,00010111101101111011111001000011
820  DATA68,01110001101100011000010110001001
830  DATA56,00101000000000101011100010011110
840  DATA193,11101100011000111111001000100110
850  DATA87,11110101000011111100010001010111
860  DATA160,11010110110101101010001111101000
870  DATA2,11101110000011100110000100101100
880  DATA30,11111010000011110011110101100011
890  DATA7,10011110011001001001010110100011
900  DATA26,11111101011000101111100101111010
910  DATA85,00011011000000011010010101111011
920  DATA15,10010000101111110001110110010001
930  DATA201,11100010101110000111101000010100
940  DATA188,11000010110101111111111110100111
950  DATA0,00000000000000000000000000000000
960  DATA238,01000111101100101100111101111111
970  DATA181,10111011000010110100011100000011
980  DATA114,10111110000010110001000000010000```

### Using 6502 Assembly

``` 0  HIMEM: 37230
8A=37229:P\$=" 'Q\$L.L%BP#%GKSFGFB1LEZ*=!4E[-Z=!6EW-[=!TEX-W=!U-XHPR?MPN<!PJ)!7!U7!T7!607!49&^!U+!T+!6+!43 =!UIM7!U=!TI87!T=!6IC7!6=!4I 7!4/POAP;<D2(Q>5ZIYUZ0PV@"
9FORI=1TOLEN(P\$):B\$=MID\$("D2A0--A6Q4Q5A8Q7Q8Q9R0M6--N3N4N6N8R7O2O4O6S1O7P7S4Q0--S7Q2S9U2X0J6X2X8N1A4G9T8X9U0H3H4Y0X6X7U6U7U8O5V0L5O8O9Y6Z2Z3Z5Z0Z1----J4",(ASC(MID\$(P\$,I))-32)*2+1,2):POKEA+I,(ASC(MID\$(B\$,1))-65)*10+ASC(MID\$(B\$,2))-48:NEXT
100 S\$ = "THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG"
110  FOR I = 2 TO  LEN (S\$)
120 C =  ASC ( MID\$ (S\$,I,1))
130 C\$ =  CHR\$ (C + 32 * (C >  =  ASC ("A") AND C <  =  ASC ("Z")))
140 S\$ =  LEFT\$ (S\$,I - 1) + C\$ +  MID\$ (S\$,I + 1, LEN (S\$) - I)
150  NEXT
155  PRINT  MID\$ (S\$,1,0 *  FRE (0));
160  POKE 236, PEEK (131)
170  POKE 237, PEEK (132)
180 A =  PEEK (236) +  PEEK (237) * 256
190  POKE 236, PEEK (A + 1)
200  POKE 237, PEEK (A + 2)
210  POKE 238, PEEK (A)
220  POKE 239,0
230  FOR I = 250 TO 253
240  POKE I,0
250  NEXT
260  CALL 37230
270  FOR I = 253 TO 250 STEP  - 1
280 B =  PEEK (I)
290  FOR J = 0 TO 1
300  PRINT  MID\$ ("0123456789ABCDEF",B / 16 + 1,1);
310 B = (B -  INT (B / 16) * 16) * 16
320  NEXT J,I```

## AutoHotkey

### DllCall / WinAPI

```CRC32(str, enc = "UTF-8")
{
l := (enc = "CP1200" || enc = "UTF-16") ? 2 : 1, s := (StrPut(str, enc) - 1) * l
VarSetCapacity(b, s, 0) && StrPut(str, &b, floor(s / l), enc)
CRC32 := DllCall("ntdll.dll\RtlComputeCrc32", "UInt", 0, "Ptr", &b, "UInt", s)
return Format("{:#x}", CRC32)
}

MsgBox % CRC32("The quick brown fox jumps over the lazy dog")
```
Output:
`0x414fa339`

### Implementation

```CRC32(str)
{
static table := []
loop 256 {
crc := A_Index - 1
loop 8
crc := (crc & 1) ? (crc >> 1) ^ 0xEDB88320 : (crc >> 1)
table[A_Index - 1] := crc
}
crc := ~0
loop, parse, str
crc := table[(crc & 0xFF) ^ Asc(A_LoopField)] ^ (crc >> 8)
return Format("{:#x}", ~crc)
}

MsgBox % CRC32("The quick brown fox jumps over the lazy dog")
```
Output:
`0x414fa339`

## C

### Library

Using zlib's crc32:

```#include <stdio.h>
#include <string.h>
#include <zlib.h>

int main()
{
const char *s = "The quick brown fox jumps over the lazy dog";
printf("%lX\n", crc32(0, (const void*)s, strlen(s)));

return 0;
}
```

### Implementation

This code is a translation from Ruby, with an adjustment to use 32-bit integers. This code happens to resemble the examples from RFC 1952 section 8 and from PNG annex D, because those examples use an identical table.

```#include <inttypes.h>
#include <stdio.h>
#include <string.h>

uint32_t
rc_crc32(uint32_t crc, const char *buf, size_t len)
{
static uint32_t table[256];
static int have_table = 0;
uint32_t rem;
uint8_t octet;
int i, j;
const char *p, *q;

/* This check is not thread safe; there is no mutex. */
if (have_table == 0) {
/* Calculate CRC table. */
for (i = 0; i < 256; i++) {
rem = i;  /* remainder from polynomial division */
for (j = 0; j < 8; j++) {
if (rem & 1) {
rem >>= 1;
rem ^= 0xedb88320;
} else
rem >>= 1;
}
table[i] = rem;
}
have_table = 1;
}

crc = ~crc;
q = buf + len;
for (p = buf; p < q; p++) {
octet = *p;  /* Cast to unsigned octet. */
crc = (crc >> 8) ^ table[(crc & 0xff) ^ octet];
}
return ~crc;
}

int
main()
{
const char *s = "The quick brown fox jumps over the lazy dog";
printf("%" PRIX32 "\n", rc_crc32(0, s, strlen(s)));

return 0;
}
```

## C#

```    /// <summary>
/// Performs 32-bit reversed cyclic redundancy checks.
/// </summary>
public class Crc32
{
#region Constants
/// <summary>
/// Generator polynomial (modulo 2) for the reversed CRC32 algorithm.
/// </summary>
private const UInt32 s_generator = 0xEDB88320;
#endregion

#region Constructors
/// <summary>
/// Creates a new instance of the Crc32 class.
/// </summary>
public Crc32()
{
// Constructs the checksum lookup table. Used to optimize the checksum.
m_checksumTable = Enumerable.Range(0, 256).Select(i =>
{
var tableEntry = (uint)i;
for (var j = 0; j < 8; ++j)
{
tableEntry = ((tableEntry & 1) != 0)
? (s_generator ^ (tableEntry >> 1))
: (tableEntry >> 1);
}
return tableEntry;
}).ToArray();
}
#endregion

#region Methods
/// <summary>
/// Calculates the checksum of the byte stream.
/// </summary>
/// <param name="byteStream">The byte stream to calculate the checksum for.</param>
/// <returns>A 32-bit reversed checksum.</returns>
public UInt32 Get<T>(IEnumerable<T> byteStream)
{
try
{
// Initialize checksumRegister to 0xFFFFFFFF and calculate the checksum.
return ~byteStream.Aggregate(0xFFFFFFFF, (checksumRegister, currentByte) =>
(m_checksumTable[(checksumRegister & 0xFF) ^ Convert.ToByte(currentByte)] ^ (checksumRegister >> 8)));
}
catch (FormatException e)
{
throw new CrcException("Could not read the stream out as bytes.", e);
}
catch (InvalidCastException e)
{
throw new CrcException("Could not read the stream out as bytes.", e);
}
catch (OverflowException e)
{
throw new CrcException("Could not read the stream out as bytes.", e);
}
}
#endregion

#region Fields
/// <summary>
/// Contains a cache of calculated checksum chunks.
/// </summary>

#endregion
}
```

Test:

```	var arrayOfBytes = Encoding.ASCII.GetBytes("The quick brown fox jumps over the lazy dog");

var crc32 = new Crc32();
Console.WriteLine(crc32.Get(arrayOfBytes).ToString("X"));
```
Output:

414fa339

## C++

```#include <array>
#include <ranges>
#include <cstdint>
#include <numeric>
#include <concepts>
#include <algorithm>

// These headers are only needed for main(), to demonstrate.
#include <iomanip>
#include <iostream>
#include <string_view>

inline constexpr auto crc_table = []() {
std::array<std::uint32_t, 256> retval{};
std::generate(retval.begin(), retval.end(),
[n = std::uint32_t{ 0 }]() mutable {
auto c = n++;
for (std::uint8_t k = 0; k < 8; ++k) {
if (c & 1) c = std::uint32_t{ 0xedb88320 } ^ (c >> 1);
else c >>= 1;
}
return c;
});
return retval;
}();

[[nodiscard]] constexpr std::uint32_t crc(const std::ranges::input_range auto& rng)
noexcept requires std::convertible_to<std::ranges::range_value_t<decltype(rng)>, std::uint8_t> {
return ~std::accumulate(std::ranges::begin(rng), std::ranges::end(rng),
~std::uint32_t{ 0 } & std::uint32_t{ 0xff'ff'ff'ffu },
[](std::uint32_t checksum, std::uint8_t value)
{ return crc_table[(checksum ^ value) & 0xff] ^ (checksum >> 8); });
}

int main() {
constexpr std::string_view str = "The quick brown fox jumps over the lazy dog";

std::cout << std::hex << std::setw(8) << std::setfill('0') << crc(str) << '\n';
}
```
Output:
```414fa339
```
```"The quick brown fox jumps over the lazy dog"
(to hex ...)
54686520717569636B2062726F776E20666F78206A756D7073206F76657220746865206C617A7920646F67 414FA339
[other useful test vectors]
FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF FF6CAB0B
000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F 91267E8A
```
Library: boost
```#include <boost\crc.hpp>
#include <string>
#include <iostream>

int main()
{
std::string str( "The quick brown fox jumps over the lazy dog" );
boost::crc_32_type  crc;
crc.process_bytes( str.data(), str.size() );

std::cout << "Checksum: " << std::hex << crc.checksum() << std::endl;
return 0;
}
```
Output:
```Checksum: 414fa339
```

## Clojure

Translation of: Java
```(let [crc (new java.util.zip.CRC32)
str "The quick brown fox jumps over the lazy dog"]
(. crc update (. str getBytes))
(printf "CRC-32('%s') = %s\n" str (Long/toHexString (. crc getValue))))
```
Output:
```CRC-32('The quick brown fox jumps over the lazy dog') = 414fa339
```

## COBOL

Works with: GnuCOBOL
Library: zlib
```      *> tectonics: cobc -xj crc32-zlib.cob -lz
identification division.
program-id. rosetta-crc32.

environment division.
configuration section.
repository.
function all intrinsic.

data division.
working-storage section.
01 crc32-initial        usage binary-c-long.
01 crc32-result         usage binary-c-long unsigned.
01 crc32-input.
05 value "The quick brown fox jumps over the lazy dog".
01 crc32-hex            usage pointer.

procedure division.
crc32-main.

*> libz crc32
call "crc32" using
by value crc32-initial
by reference crc32-input
by value length(crc32-input)
returning crc32-result
on exception
display "error: no crc32 zlib linkage" upon syserr
end-call
call "printf" using "checksum: %lx" & x"0a" by value crc32-result

*> GnuCOBOL pointers are displayed in hex by default
set crc32-hex up by crc32-result
display 'crc32 of "' crc32-input '" is ' crc32-hex

goback.
end program rosetta-crc32.
```
Output:
```prompt\$ cobc -xj crc32-zlib.cob -lz
checksum: 414fa339
crc32 of "The quick brown fox jumps over the lazy dog" is 0x00000000414fa339
```

## CoffeeScript

Allows the specification of the initial CRC value, which defaults to 0xFFFFFFFF. Optimized for speed and terseness (then readability/indentation).

```crc32 = do ->
table =
for n in [0..255]
for [0..7]
if n & 1
n = 0xEDB88320 ^ n >>> 1
else
n >>>= 1
n
(str, crc = -1) ->
for c in str
crc = crc >>> 8 ^ table[(crc ^ c.charCodeAt 0) & 255]
(crc ^ -1) >>> 0
```

Test:

```console.log (crc32 'The quick brown fox jumps over the lazy dog').toString 16
```

Output:

```414fa339
```

## Common Lisp

```(ql:quickload :ironclad)
(defun string-to-digest (str digest)
"Return the specified digest for the ASCII string as a hex string."

(string-to-digest "The quick brown fox jumps over the lazy dog" :crc32)
```
Output:
`"414fa339"`

## Component Pascal

BlackBox Component Builder
Require ZLib Subsystem

```MODULE BbtComputeCRC32;
IMPORT ZlibCrc32,StdLog;

PROCEDURE Do*;
VAR
s: ARRAY 128 OF SHORTCHAR;
BEGIN
s := "The quick brown fox jumps over the lazy dog";
StdLog.IntForm(ZlibCrc32.CRC32(0,s,0,LEN(s\$)),16,12,'0',TRUE);
StdLog.Ln;
END Do;
END BbtComputeCRC32.```

Execute: ^Q BbtComputeCRC32.Do

Output:
```0414FA339%16
```

## Crystal

```require "digest/crc32";

p Digest::CRC32.checksum("The quick brown fox jumps over the lazy dog").to_s(16)
```
Output:
```"414fa339"
```

## D

```void main() {
import std.stdio, std.digest.crc;

"The quick brown fox jumps over the lazy dog"
.crc32Of.crcHexString.writeln;
}
```
Output:
`414FA339`

## Delphi

```program CalcCRC32;

{\$APPTYPE CONSOLE}

uses
System.SysUtils, System.ZLib;

var
Data: AnsiString = 'The quick brown fox jumps over the lazy dog';
CRC: UInt32;

begin
CRC := crc32(0, @Data[1], Length(Data));
WriteLn(Format('CRC32 = %8.8X', [CRC]));
end.
```
Output:
`CRC32 = 414FA339`

## Elixir

```defmodule Test do
def crc32(str) do
IO.puts :erlang.crc32(str) |> Integer.to_string(16)
end
end

Test.crc32("The quick brown fox jumps over the lazy dog")
```
Output:
```414FA339
```

## Erlang

Using the built-in crc32 implementation.

```-module(crc32).
-export([test/0]).
test() ->
io:fwrite("~.16#~n",[erlang:crc32(<<"The quick brown fox jumps over the lazy dog">>)]).
```
Output:
```16#414FA339
```

## F#

```module Crc32 =

open System

// Generator polynomial (modulo 2) for the reversed CRC32 algorithm.
let private s_generator = uint32 0xEDB88320

// Generate lookup table
let private lutIntermediate input =
if (input &&& uint32 1) <> uint32 0
then s_generator ^^^ (input >>> 1)
else input >>> 1

let private lutEntry input =
{0..7}
|> Seq.fold (fun acc x -> lutIntermediate acc) input

let private crc32lut =
[uint32 0 .. uint32 0xFF]
|> List.map lutEntry

let crc32byte (register : uint32) (byte : byte) =
crc32lut.[Convert.ToInt32((register &&& uint32 0xFF) ^^^ Convert.ToUInt32(byte))] ^^^ (register >>> 8)

// CRC32 of a byte array
let crc32 (input : byte[]) =
let result = Array.fold crc32byte (uint32 0xFFFFFFFF) input
~~~result

// CRC32 from ASCII string
let crc32OfAscii (inputAscii : string) =
let bytes = System.Text.Encoding.ASCII.GetBytes(inputAscii)
crc32 bytes

// Test
let testString = "The quick brown fox jumps over the lazy dog"
printfn "ASCII Input: %s" testString
let result = crc32OfAscii testString
printfn "CRC32: 0x%x" result
```
Output:
```ASCII Input: The quick brown fox jumps over the lazy dog
CRC32: 0x414fa339
```

## Factor

Like SHA-1#Factor, but with crc32.

```IN: scratchpad USING: checksums checksums.crc32 ;
IN: scratchpad "The quick brown fox jumps over the lazy dog" crc32
checksum-bytes hex-string .
"414fa339"
```

The implementation is at core/checksums/crc32/crc32.factor.

## FBSL

```#APPTYPE CONSOLE

PRINT HEX(CHECKSUM("The quick brown fox jumps over the lazy dog"))

PAUSE
```
Output:
```414FA339

Press any key to continue...```

## Forth

This code can implement other types of CRC by using other polynomial constants: use \$8408 for CCITT CRC-16, or \$a001 for IBM CRC-16.

```: crc/ ( n -- n ) 8 0 do dup 1 rshift swap 1 and if \$edb88320 xor then loop ;

: crcfill   256 0 do i crc/ , loop ;

create crctbl crcfill

: crc+ ( crc n -- crc' ) over xor \$ff and  cells crctbl + @  swap 8 rshift xor ;

: crcbuf ( crc str len -- crc ) bounds ?do i c@ crc+ loop ;

\$ffffffff s" The quick brown fox jumps over the lazy dog" crcbuf \$ffffffff xor hex.  bye   \ \$414FA339
```

## Fortran

```module crc32_m
use iso_fortran_env
implicit none
integer(int32) :: crc_table(0:255)
contains
subroutine update_crc(a, crc)
integer :: n, i
character(*) :: a
integer(int32) :: crc

crc = not(crc)
n = len(a)
do i = 1, n
crc = ieor(shiftr(crc, 8), crc_table(iand(ieor(crc, iachar(a(i:i))), 255)))
end do
crc = not(crc)
end subroutine

subroutine init_table
integer :: i, j
integer(int32) :: k

do i = 0, 255
k = i
do j = 1, 8
if (btest(k, 0)) then
k = ieor(shiftr(k, 1), -306674912)
else
k = shiftr(k, 1)
end if
end do
crc_table(i) = k
end do
end subroutine
end module

program crc32
use crc32_m
implicit none
integer(int32) :: crc = 0
character(*), parameter :: s = "The quick brown fox jumps over the lazy dog"
call init_table
call update_crc(s, crc)
print "(Z8)", crc
end program
```

## FreeBASIC

Translation of: C
```' version 18-03-2017
' compile with: fbc -s console

Function crc32(buf As String) As UInteger<32>

Static As UInteger<32> table(256)
Static As UInteger<32> have_table
Dim As UInteger<32> crc, k
Dim As ULong i, j

If have_table = 0 Then
For i = 0 To 255
k = i
For j = 0 To 7
If (k And 1) Then
k Shr= 1
k Xor= &Hedb88320
Else
k Shr= 1
End If
table(i) = k
Next
Next
have_table = 1
End If

crc = Not crc ' crc = &Hffffffff

For i = 0 To Len(buf) -1
crc = (crc Shr 8) Xor table((crc And &hff) Xor buf[i])
Next

Return Not crc

End Function

' ------=< MAIN >=------

Dim As String l = "The quick brown fox jumps over the lazy dog"
Dim As UInteger<32> crc

Print "input = "; l
print
Print "The CRC-32 checksum = "; Hex(crc32(l), 8)

' empty keyboard buffer
While Inkey <> "" : Wend
Print : Print "hit any key to end program"
Sleep
End```
Output:
```input = The quick brown fox jumps over the lazy dog

The CRC-32 checksum = 414FA339```

## Go

### Library

```package main

import (
"fmt"
"hash/crc32"
)

func main() {
s := []byte("The quick brown fox jumps over the lazy dog")
result := crc32.ChecksumIEEE(s)
fmt.Printf("%X\n", result)
}
```
Output:
`414FA339`

### Implementation

```package main

import "fmt"

var table [256]uint32

func init() {
for i := range table {
word := uint32(i)
for j := 0; j < 8; j++ {
if word&1 == 1 {
word = (word >> 1) ^ 0xedb88320
} else {
word >>= 1
}
}
table[i] = word
}
}

func crc32(s string) uint32 {
crc := ^uint32(0)
for i := 0; i < len(s); i++ {
crc = table[byte(crc)^s[i]] ^ (crc >> 8)
}
return ^crc
}

func main() {
fmt.Printf("%0x\n", crc32("The quick brown fox jumps over the lazy dog"))
}
```
Output:
```414fa339
```

## Groovy

```def crc32(byte[] bytes) {
new java.util.zip.CRC32().with { update bytes; value }
}
```

Testing:

```assert '414FA339' == sprintf('%04X', crc32('The quick brown fox jumps over the lazy dog'.bytes))
```

```import Data.Bits ((.&.), complement, shiftR, xor)
import Data.Word (Word32)
import Numeric (showHex)

crcTable :: Word32 -> Word32
crcTable = (table !!) . fromIntegral
where
table = ((!! 8) . iterate xf) <\$> [0 .. 255]
shifted x = shiftR x 1
xf r
| r .&. 1 == 1 = xor (shifted r) 0xedb88320
| otherwise = shifted r

charToWord :: Char -> Word32

calcCrc :: String -> Word32
calcCrc = complement . foldl cf (complement 0)
where
cf crc x = xor (shiftR crc 8) (crcTable \$ xor (crc .&. 0xff) (charToWord x))

crc32 :: String -> String
crc32 = flip showHex [] . calcCrc

main :: IO ()
main = putStrLn \$ crc32 "The quick brown fox jumps over the lazy dog"
```
Output:
`414fa339`

Using the zlib C library ( compile with "ghc -lz file.hs"):

```import Data.List (genericLength)
import Numeric (showHex)
import Foreign.C

foreign import ccall "zlib.h crc32" zlib_crc32 ::
CULong -> CString -> CUInt -> CULong

main :: IO ()
main = do
let s = "The quick brown fox jumps over the lazy dog"
ptr <- newCString s
let r = zlib_crc32 0 ptr (genericLength s)
putStrLn \$ showHex r ""
```
Output:
`414fa339`

## Haxe

```using StringTools;

class Main {
static function main() {
var data = haxe.io.Bytes.ofString("The quick brown fox jumps over the lazy dog");
var crc = haxe.crypto.Crc32.make(data);
Sys.println(crc.hex());
}
}
```
Output:
`414FA339`

## Icon and Unicon

There is no library function for this so we implement one. Icon/Unicon binary operations apply to large integers so we need to mask to the desired unsigned word size. This also only applies to full bytes.

```link hexcvt,printf

procedure main()
s := "The quick brown fox jumps over the lazy dog"
a := "414FA339"
printf("crc(%i)=%s - implementation is %s\n",
s,r := crc32(s),if r == a then "correct" else "in error")
end

procedure crc32(s)      #: return crc-32 (ISO 3309, ITU-T V.42, Gzip, PNG) of s
initial {
crcL := list(256)                            # crc table
p := [0,1,2,4,5,7,8,10,11,12,16,22,23,26]    # polynomial terms
every (poly := 0) := ior(poly,ishift(1,31-p[1 to *p]))
every c := n := 0 to *crcL-1 do {            # table
every 1 to 8 do
if iand(c,1) = 1 then
ixor(poly,ishift(c,-1))
else
ishift(c,-1)
)
crcL[n+1] := c
}
}

crc := ixor(0,mask)                          # invert bits
ixor(crcL[iand(255,ixor(crc,ord(!s)))+1],ishift(crc,-8)))
end
```

hexcvt.icn (provides hex and hexstring) printf.icn (provides formatting)

Output:
`crc("The quick brown fox jumps over the lazy dog")=414FA339 - implementation is correct`

## J

```   ((i.32) e. 32 26 23 22 16 12 11 10 8 7 5 4 2 1 0) 128!:3 'The quick brown fox jumps over the lazy dog'
_3199229127
```

Other possible representations of this result:

```   (2^32x)|((i.32) e. 32 26 23 22 16 12 11 10 8 7 5 4 2 1 0) 128!:3 'The quick brown fox jumps over the lazy dog'
1095738169
require'convert'
hfd (2^32x)|((i.32) e. 32 26 23 22 16 12 11 10 8 7 5 4 2 1 0) 128!:3 'The quick brown fox jumps over the lazy dog'
414FA339
```

## Java

```import java.util.zip.CRC32;
```
```public static void main(String[] args) throws IOException {
String string = "The quick brown fox jumps over the lazy dog";
CRC32 crc = new CRC32();
crc.update(string.getBytes());
System.out.printf("%x", crc.getValue());
}
```
Output:
```414fa339
```

## JavaScript

```(() => {
'use strict';

// --------------------- CRC-32 ----------------------

// crc32 :: String -> Int
const crc32 = str => {
// table :: [Int]
const table = enumFromTo(0)(255).map(
n => take(9)(
iterate(
x => (
x & 1 ? (
z => 0xEDB88320 ^ z
) : identity
)(x >>> 1)
)(n)
)[8]
);
return chars(str).reduce(
(a, c) => (a >>> 8) ^ table[
(a ^ c.charCodeAt(0)) & 255
],
-1
) ^ -1;
};

// ---------------------- TEST -----------------------
// main :: IO ()
const main = () =>
showHex(
crc32('The quick brown fox jumps over the lazy dog')
);

// --------------------- GENERIC ---------------------

// chars :: String -> [Char]
const chars = s =>
s.split('');

// enumFromTo :: Int -> Int -> [Int]
const enumFromTo = m =>
n => !isNaN(m) ? (
Array.from({
length: 1 + n - m
}, (_, i) => m + i)
) : enumFromTo_(m)(n);

// identity :: a -> a
const identity = x =>
// The identity function.
x;

// iterate :: (a -> a) -> a -> Gen [a]
const iterate = f =>
// An infinite list of repeated
// applications of f to x.
function* (x) {
let v = x;
while (true) {
yield(v);
v = f(v);
}
};

// showHex :: Int -> String
const showHex = n =>
// Hexadecimal string for a given integer.
'0x' + n.toString(16);

// take :: Int -> [a] -> [a]
// take :: Int -> String -> String
const take = n =>
// The first n elements of a list,
// string of characters, or stream.
xs => 'GeneratorFunction' !== xs
.constructor.constructor.name ? (
xs.slice(0, n)
) : [].concat.apply([], Array.from({
length: n
}, () => {
const x = xs.next();
return x.done ? [] : [x.value];
}));

// MAIN -------------
const result = main();
return (
console.log(result),
result
);
})();
```
Output:
`0x414fa339`

## Jsish

From the shell

```# Util.crc32('The quick brown fox jumps over the lazy dog').toString(16);
```
Output:
`"414fa339"`

## Julia

### Using the zlib Library

```using Libz
println(string(Libz.crc32(UInt8.(b"The quick brown fox jumps over the lazy dog")), base=16))
```
Output:
```414fa339
```

### Source Implementation

Works with: Julia version 0.6
```function crc32(crc::Int, str::String)
table = zeros(UInt32, 256)

for i in 0:255
tmp = i
for j in 0:7
if tmp & 1 == 1
tmp >>= 1
tmp ⊻= 0xedb88320
else
tmp >>= 1
end
end

table[i + 1] = tmp
end

crc ⊻= 0xffffffff

for i in UInt32.(collect(str))
crc = (crc >> 8) ⊻ table[(crc & 0xff) ⊻ i + 1]
end

crc ⊻ 0xffffffff
end

str = "The quick brown fox jumps over the lazy dog"
crc = crc32(0, str)
assert(crc == 0x414fa339)
println("Message: ", str)
println("Checksum: ", hex(crc))
```
Output:
```Message: The quick brown fox jumps over the lazy dog
Checksum: 414fa339```

## Kotlin

```// version 1.0.6

import java.util.zip.CRC32

fun main(args: Array<String>) {
val text = "The quick brown fox jumps over the lazy dog"
val crc = CRC32()
with (crc) {
update(text.toByteArray())
println("The CRC-32 checksum of '\$text' = \${"%x".format(value)}")
}
}
```
Output:
```The CRC-32 checksum of 'The quick brown fox jumps over the lazy dog' = 414fa339
```

## Lingo

### Pure Lingo

```crcObj = script("CRC").new()

crc32 = crcObj.crc32("The quick brown fox jumps over the lazy dog")

put crc32
-- <ByteArrayObject length = 4 ByteArray = 0x41, 0x4f, 0xa3, 0x39 >

put crc32.toHexString(1, crc32.length)
-- "41 4f a3 39"```

Implementation:

```--****************************************************************************
-- @desc      CRC-32 Class
-- @file      parent script "CRC"
-- @version   0.1
--****************************************************************************

property _CRC32Table

----------------------------------------
-- @constructor
----------------------------------------
on new me

-- used for fast CRC32 calculation
me._CRC32Table = [\
0, 1996959894, -301047508, -1727442502, 124634137, 1886057615, -379345611, -1637575261, 249268274, 2044508324,\
-522852066, -1747789432, 162941995, 2125561021, -407360249, -1866523247, 498536548, 1789927666, -205950648,\
-2067906082, 450548861, 1843258603, -187386543, -2083289657, 325883990, 1684777152, -43845254, -1973040660,\
335633487, 1661365465, -99664541, -1928851979, 997073096, 1281953886, -715111964, -1570279054, 1006888145,\
1258607687, -770865667, -1526024853, 901097722, 1119000684, -608450090, -1396901568, 853044451, 1172266101,\
-589951537, -1412350631, 651767980, 1373503546, -925412992, -1076862698, 565507253, 1454621731, -809855591,\
-1195530993, 671266974, 1594198024, -972236366, -1324619484, 795835527, 1483230225, -1050600021, -1234817731,\
1994146192, 31158534, -1731059524, -271249366, 1907459465, 112637215, -1614814043, -390540237, 2013776290,\
251722036, -1777751922, -519137256, 2137656763, 141376813, -1855689577, -429695999, 1802195444, 476864866,\
-2056965928, -228458418, 1812370925, 453092731, -2113342271, -183516073, 1706088902, 314042704, -1950435094,\
-54949764, 1658658271, 366619977, -1932296973, -69972891, 1303535960, 984961486, -1547960204, -725929758,\
1256170817, 1037604311, -1529756563, -740887301, 1131014506, 879679996, -1385723834, -631195440, 1141124467,\
855842277, -1442165665, -586318647, 1342533948, 654459306, -1106571248, -921952122, 1466479909, 544179635,\
-1184443383, -832445281, 1591671054, 702138776, -1328506846, -942167884, 1504918807, 783551873, -1212326853,\
-1061524307, -306674912, -1698712650, 62317068, 1957810842, -355121351, -1647151185, 81470997, 1943803523,\
-480048366, -1805370492, 225274430, 2053790376, -468791541, -1828061283, 167816743, 2097651377, -267414716,\
-2029476910, 503444072, 1762050814, -144550051, -2140837941, 426522225, 1852507879, -19653770, -1982649376,\
282753626, 1742555852, -105259153, -1900089351, 397917763, 1622183637, -690576408, -1580100738, 953729732,\
1340076626, -776247311, -1497606297, 1068828381, 1219638859, -670225446, -1358292148, 906185462, 1090812512,\
-547295293, -1469587627, 829329135, 1181335161, -882789492, -1134132454, 628085408, 1382605366, -871598187,\
-1156888829, 570562233, 1426400815, -977650754, -1296233688, 733239954, 1555261956, -1026031705, -1244606671,\
752459403, 1541320221, -1687895376, -328994266, 1969922972, 40735498, -1677130071, -351390145, 1913087877,\
83908371, -1782625662, -491226604, 2075208622, 213261112, -1831694693, -438977011, 2094854071, 198958881,\
-2032938284, -237706686, 1759359992, 534414190, -2118248755, -155638181, 1873836001, 414664567, -2012718362,\
-15766928, 1711684554, 285281116, -1889165569, -127750551, 1634467795, 376229701, -1609899400, -686959890,\
1308918612, 956543938, -1486412191, -799009033, 1231636301, 1047427035, -1362007478, -640263460, 1088359270,\
936918000, -1447252397, -558129467, 1202900863, 817233897, -1111625188, -893730166, 1404277552, 615818150,\
-1160759803, -841546093, 1423857449, 601450431, -1285129682, -1000256840, 1567103746, 711928724, -1274298825,\
-1022587231, 1510334235, 755167117]
return me
end

----------------------------------------
-- Calculates CRC-32 checksum of string or bytearray
-- @param {bytearray|string} input
-- @return {bytearray} (4 bytes)
----------------------------------------
on crc32 (me, input)
if stringP(input) then input = bytearray(input)
crc = -1
len = input.length
repeat with i = 1 to len
if (crc>0) then bitShift8 = crc/256
else bitShift8 = bitAnd(crc,2147483647)/256+8388608
crc = bitXor(bitShift8,me._CRC32Table[bitAnd(bitXor(crc,input[i]),255)+1])
end repeat
ba = bytearray()
ba.endian = #bigEndian
ba.writeInt32(bitXOr(crc,-1))
ba.position = 1
return ba
end```

### Using an "Xtra" (=binary plugin)

```cx = Xtra("Crypto").new()
put cx.cx_crc32_string("The quick brown fox jumps over the lazy dog")
-- "414fa339"```

## Lua

### Using Library

```local compute=require"zlib".crc32()
local sum=compute("The quick brown fox jumps over the lazy dog")
print(string.format("0x%x", sum))
```
Output:

0x414fa339

### Implementation

```function crc32(buf, size)
local crc = 0xFFFFFFFF
local table = {}
local rem, c

-- calculate CRC-table
for i = 0, 0xFF do
rem = i
for j = 1, 8 do
if (rem & 1 == 1) then
rem = rem >> 1
rem = rem ~ 0xEDB88320
else
rem = rem >> 1
end
end
table[i] = rem
end

for x = 1, size do
c = buf[x]
crc = (crc >> 8) ~ table[(crc & 0xFF) ~ c]
end
return crc ~ 0xFFFFFFFF
end

local str = "The quick brown fox jumps over the lazy dog"
local t = {}
for i = 1, #str do
t[i] = str:byte(i)
end

print(string.format("CRC32: %x", crc32(t,#str)))
```
Output:

CRC32: 414fa339

## M2000 Interpreter

### Using Code

```Module CheckIt {
Function PrepareTable {
Dim Base 0, table(256)
For i = 0 To 255 {
k = i
For j = 0 To 7 {
If binary.and(k,1)=1 Then {
k =binary.Xor(binary.shift(k, -1) ,  0xEDB88320)
}  Else k=binary.shift(k, -1)
}
table(i) = k
}
=table()
}
crctable=PrepareTable()
crc32= lambda crctable (buf\$) -> {
crc =0xFFFFFFFF
For i = 0 To Len(buf\$) -1
crc = binary.xor(binary.shift(crc, -8), array(crctable, binary.xor(binary.and(crc, 0xff), asc(mid\$(buf\$, i+1, 1)))))
Next i
=0xFFFFFFFF-crc
}
Print crc32("The quick brown fox jumps over the lazy dog")=0x414fa339
}
CheckIt```

### Using Api

```Module CheckApi {
Declare CRC32 LIB "ntdll.RtlComputeCrc32" {Long Zero, a\$, long s}
a\$=Str\$("The quick brown fox jumps over the lazy dog")
l=len(a\$)*2
Hex Uint(CRC32(0,a\$,l))
}
CheckApi```

## Mathematica / Wolfram Language

```type="CRC32"; (*pick one out of 13 predefined hash types*)
StringForm[
"The "<>type<>" hash code of \"``\" is ``.",
s="The quick brown fox jumps over the lazy dog",
Hash[s,type,"HexString"]
]
```
Output:
```The CRC32 hash code of "The quick brown fox jumps over the lazy dog" is 414fa339.
```

## Neko

The NekoVM is a 31 bit machine; 30 signed. Loadable primitives handle 32bit integers. The zlib library API exposes a CRC-32 function, that expects and returns Int32.

```/**
<doc>CRC32 in Neko</doc>
**/

var crc = int32_new(0)
var txt = "The quick brown fox jumps over the lazy dog"

crc = update_crc32(crc, txt, 0, \$ssize(txt))
\$print(crc, "\n")
```
Output:
```prompt\$ nekoc crc32.neko
prompt\$ neko crc32.n
1095738169
prompt\$ dc -e "\$(neko crc32.n) 16op"
414FA339```

## NetRexx

Translation of: Java
```/* NetRexx */
options replace format comments java crossref symbols binary

import java.util.zip.CRC32

toBeEncoded = String("The quick brown fox jumps over the lazy dog")
myCRC = CRC32()
myCRC.update(toBeEncoded.getBytes())
say "The CRC-32 value is :" Long.toHexString(myCRC.getValue()) "!"

return```
Output:
```The CRC-32 value is : 414fa339 !
```

## Nim

```import strutils

type TCrc32* = uint32
const InitCrc32* = TCrc32(0xffffffff)

proc createCrcTable(): array[0..255, TCrc32] =
for i in 0..255:
var rem = TCrc32(i)
for j in 0..7:
if (rem and 1) > 0: rem = (rem shr 1) xor TCrc32(0xedb88320)
else: rem = rem shr 1
result[i] = rem

# Table created at compile time
const crc32table = createCrcTable()

proc crc32(s: string): TCrc32 =
result = InitCrc32
for c in s:
result = (result shr 8) xor crc32table[(result and 0xff) xor byte(c)]
result = not result

echo crc32("The quick brown fox jumps over the lazy dog").int64.toHex(8)
```
Output:
`414FA339`

## NOWUT

```; link with PIOxxx.OBJ

sectionbss

crctable.d:     resd 256

sectiondata

havetable.b:    db 0
string:         db "The quick brown fox jumps over the lazy dog"
stringend:
db 13,10,0        ; carriage return and null terminator

sectioncode

start!
gosub initplatform

beginfunc
localvar crc.d

callex ,printnt,"input = ".a
callex ,printnt,string

callex ,printnt,"The CRC-32 checksum = ".a
callex crc,crc32,string,stringend
callex ,printhexr,crc

endfunc
end

crc32:
beginfunc bufend.d,buf.d
localvar i.d,j.d,k.d,k2.d,crc.d

ifunequal havetable,0,tabledone
i=0
whileless i,256

k=i > j=8
countdown j
k2=k > k=_ shr 1
ifequal k2 and 1,0,noxor > k=_ xor \$EDB88320
noxor:
nextcount

crctable(i shl 2)=k
i=_+1
wend

havetable=1
tabledone:

crc=-1

whileless buf,bufend
crc=_ shr 8 xor crctable(crc and \$FF xor [buf].b shl 2)
buf=_+1
wend

crc=_ xor -1
endfunc crc
returnex 8                        ; clean off 2 parameters from the stack```
Output:
```input = The quick brown fox jumps over the lazy dog
The CRC-32 checksum = 414FA339```

## Oberon-2

Works with: oo2c Version 2
```MODULE CRC32;
IMPORT
NPCT:Zlib,
Strings,
Out;
VAR
s: ARRAY 128 OF CHAR;
BEGIN
COPY("The quick brown fox jumps over the lazy dog",s);
Out.Hex(Zlib.CRC32(0,s,0,Strings.Length(s)),0);Out.Ln
END CRC32.```
Output:
```414FA339
```

## Objeck

```class CRC32 {
function : Main(args : String[]) ~ Nil {
"The quick brown fox jumps over the lazy dog"->ToByteArray()->CRC32()->PrintLine();
}
}```
Output:
```1095738169
```

## OCaml

Library: camlzip
```let () =
let s = "The quick brown fox jumps over the lazy dog" in
let crc = Zlib.update_crc 0l s 0 (String.length s) in
Printf.printf "crc: %lX\n" crc
```

Running this code in interpreted mode:[[Media:Insert non-formatted text here]][[File:[Example.jpg][http://www.example.com link title]]]

```\$ ocaml unix.cma -I +zip zip.cma crc.ml
crc: 414FA339
```

## Ol

```(define (crc32 str)
(bxor #xFFFFFFFF
(fold (lambda (crc char)
(let loop ((n 8) (crc crc) (bits char))
(if (eq? n 0)
crc
(let*((flag (band (bxor bits crc) 1))
(crc (>> crc 1))
(crc (if (eq? flag 0) crc (bxor crc #xEDB88320)))
(bits (>> bits 1)))
(loop (- n 1) crc bits)))))
#xFFFFFFFF
(string->list str))))

(print (number->string (crc32 "The quick brown fox jumps over the lazy dog") 16))
(print (number->string (crc32 (list->string (repeat #x00 32))) 16))
(print (number->string (crc32 (list->string (repeat #xFF 32))) 16))
(print (number->string (crc32 (list->string (iota 32))) 16))
```
Output:
```414fa339
ff6cab0b
91267e8a
```

## ooRexx

This Program shows how easy it is to use JAVA functionality from ooRexx. bsf4oorexx from Sourceforge https://sourceforge.net/projects/bsf4oorexx/ makes that possible.

```/* ooRexx */
clzCRC32=bsf.importClass("java.util.zip.CRC32")
myCRC32 =clzCRC32~new
toBeEncoded="The quick brown fox jumps over the lazy dog"
myCRC32~update(BsfRawBytes(toBeEncoded))
numeric digits 20
say 'The CRC-32 value of "'toBeEncoded'" is:' myCRC32~getValue~d2x

::requires "BSF.CLS"    -- get Java bridge```
Output:
`The CRC-32 value of "The quick brown fox jumps over the lazy dog" is: 414FA339`

## PARI/GP

Using Linux system library (Linux only solution)

Library: libz.so
```install("crc32", "lLsL", "crc32", "libz.so");
s = "The quick brown fox jumps over the lazy dog";
printf("%0x\n", crc32(0, s, #s))```

Output:

`414fa339`

## Pascal

### Free Pascal

```Program CheckCRC;
{\$IFDEF fpc}{\$mode Delphi}{\$ENDIF}
{\$IFDEF WINDOWS}{\$APPTYPE CONSOLE}{\$ENDIF}
uses
sysutils,crc;

function CrcString(const mystring: string) : longword;
var
crcvalue: longword;
begin
crcvalue := crc32(0,nil,0);
result := crc32(crcvalue, @mystring[1], length(mystring));
end;

var
mytext: string;
begin
myText := 'The quick brown fox jumps over the lazy dog';
writeln('crc32 = ', IntToHex(CrcString(mytext), 8));
end.
```

Output:

`crc32 = 414FA339`

## Perl

```#!/usr/bin/perl
use 5.010 ;
use strict ;
use warnings ;
use Digest::CRC qw( crc32 ) ;

my \$crc = Digest::CRC->new( type => "crc32" ) ;
\$crc->add ( "The quick brown fox jumps over the lazy dog" )  ;
say "The checksum is " . \$crc->hexdigest( ) ;
```
Output:
`The checksum is 414fa339`

## Phix

Included as demo\rosetta\crc32.exw, which also includes a thread-safe version

```with javascript_semantics
sequence table
bool have_table = false

function crc32(string s)
if not have_table then
have_table = true
table = repeat(0,256)
for i=0 to 255 do
atom rem = i
for j=1 to 8 do
if and_bits(rem,1) then
rem = xor_bits(floor(rem/2),#EDB88320)
else
rem = floor(rem/2)
end if
if rem<0 then
rem += #100000000
end if
end for
table[i+1] = rem
end for
end if
atom crc = #FFFFFFFF
for i=1 to length(s) do
crc = xor_bits(floor(crc/#100),table[xor_bits(and_bits(crc,0xff),s[i])+1])
if crc<0 then
crc += #100000000
end if
end for
return and_bits(not_bits(crc),#FFFFFFFF)
end function

string s = "The quick brown fox jumps over the lazy dog"
printf(1,"The CRC of %s is %08x\n",{s,crc32(s)})
```
Output:
```The CRC of The quick brown fox jumps over the lazy dog is 414FA339
```

## PHP

PHP has a built-in function crc32.

```printf("%x\n", crc32("The quick brown fox jumps over the lazy dog"));
```
`414fa339`

## PicoLisp

Library and implementation.

```(setq *Table
(mapcar
'((N)
(do 8
(setq N
(if (bit? 1 N)
(x| (>> 1 N) `(hex "EDB88320"))
(>> 1 N) ) ) ) )
(range 0 255) ) )

(de crc32 (Lst)
(let Crc `(hex "FFFFFFFF")
(for I (chop Lst)
(setq Crc
(x|
(get
*Table
(inc (x| (& Crc 255) (char I))) )
(>> 8 Crc) ) ) )
(x| `(hex "FFFFFFFF") Crc) ) )

(let Str "The quick brown fox jumps over the lazy dog"
(println (hex (crc32 Str)))
(println
(hex (native "libz.so" "crc32" 'N 0 Str (length Str))) ) )

(bye)```

## Pike

```string foo = "The quick brown fox jumps over the lazy dog";
write("0x%x\n", Gz.crc32(foo));
```
Output:
```0x414fa339
```

## PL/I

```*process source attributes xref or(!) nest;
crct: Proc Options(main);
/*********************************************************************
* 19.08.2013 Walter Pachl  derived from REXX
*********************************************************************/
Dcl (LEFT,LENGTH,RIGHT,SUBSTR,UNSPEC) Builtin;
Dcl SYSPRINT Print;
dcl tab(0:255) Bit(32);
Call mk_tab;
Call crc_32('The quick brown fox jumps over the lazy dog');
Call crc_32('Generate CRC32 Checksum For Byte Array Example');

crc_32: Proc(s);
/*********************************************************************
* compute checksum for s
*********************************************************************/
Dcl s Char(*);
Dcl d   Bit(32);
Dcl d1  Bit( 8);
Dcl d2  Bit(24);
Dcl cc  Char(1);
Dcl ccb Bit(8);
Dcl tib Bit(8);
Dcl ti  Bin Fixed(16) Unsigned;
Dcl k   Bin Fixed(16) Unsigned;
d=(32)'1'b;
Do k=1 To length(s);
d1=right(d,8);
d2=left(d,24);
cc=substr(s,k,1);
ccb=unspec(cc);
tib=d1^ccb;
Unspec(ti)=tib;
d='00000000'b!!d2^tab(ti);
End;
d=d^(32)'1'b;
Put Edit(s,'CRC_32=',b2x(d))(Skip,a(50),a,a);
Put Edit('decimal ',b2d(d))(skip,x(49),a,f(10));
End;

b2x: proc(b) Returns(char(8));
dcl b bit(32);
dcl b4 bit(4);
dcl i Bin Fixed(31);
dcl r Char(8) Var init('');
Do i=1 To 29 By 4;
b4=substr(b,i,4);
Select(b4);
When('0000'b) r=r!!'0';
When('0001'b) r=r!!'1';
When('0010'b) r=r!!'2';
When('0011'b) r=r!!'3';
When('0100'b) r=r!!'4';
When('0101'b) r=r!!'5';
When('0110'b) r=r!!'6';
When('0111'b) r=r!!'7';
When('1000'b) r=r!!'8';
When('1001'b) r=r!!'9';
When('1010'b) r=r!!'A';
When('1011'b) r=r!!'B';
When('1100'b) r=r!!'C';
When('1101'b) r=r!!'D';
When('1110'b) r=r!!'E';
When('1111'b) r=r!!'F';
End;
End;
Return(r);
End;

b2d: Proc(b) Returns(Dec Fixed(15));
Dcl b Bit(32);
Dcl r Dec Fixed(15) Init(0);
Dcl i Bin Fixed(16);
Do i=1 To 32;
r=r*2
If substr(b,i,1) Then
r=r+1;
End;
Return(r);
End;

mk_tab: Proc;
dcl b32 bit(32);
dcl lb  bit( 1);
dcl ccc bit(32) Init('edb88320'bx);
dcl (i,j) Bin Fixed(15);
Do i=0 To 255;
b32=(24)'0'b!!unspec(i);
Do j=0 To 7;
lb=right(b32,1);
b32='0'b!!left(b32,31);
If lb='1'b Then
b32=b32^ccc;
End;
tab(i)=b32;
End;
End;
End;```
Output:
```The quick brown fox jumps over the lazy dog       CRC_32=414FA339
decimal 1095738169
Generate CRC32 Checksum For Byte Array Example    CRC_32=D1370232
decimal 3510043186
```

## PowerBASIC

```#COMPILE EXE
#DIM ALL
#COMPILER PBCC 6

' ***********

FUNCTION CRC32(BYVAL p AS BYTE PTR, BYVAL NumBytes AS DWORD) AS DWORD
STATIC LUT() AS DWORD
LOCAL i, j, k, crc AS DWORD

IF ARRAYATTR(LUT(), 0) = 0 THEN
REDIM LUT(0 TO 255)
FOR i = 0 TO 255
k = i
FOR j = 0 TO 7
IF (k AND 1) THEN
SHIFT RIGHT k, 1
k XOR= &HEDB88320
ELSE
SHIFT RIGHT k, 1
END IF
NEXT j
LUT(i) = k
NEXT i
END IF

crc = &HFFFFFFFF

FOR i = 0 TO NumBytes - 1
k = (crc AND &HFF& XOR @p[i])
SHIFT RIGHT crc, 8
crc XOR= LUT(k)
NEXT i

FUNCTION = NOT crc
END FUNCTION

' ***********

FUNCTION PBMAIN () AS LONG
LOCAL s AS STRING
LOCAL crc AS DWORD

s = "The quick brown fox jumps over the lazy dog"
CON.PRINT "Text:  " & s
crc = CRC32(STRPTR(s), LEN(s))
CON.PRINT "CRC32: " & HEX\$(crc)
END FUNCTION```
Output:
```Text:  The quick brown fox jumps over the lazy dog
CRC32: 414FA339```

## PureBasic

Works with: PB Version 5.40
```a\$="The quick brown fox jumps over the lazy dog"

UseCRC32Fingerprint() : b\$=StringFingerprint(a\$, #PB_Cipher_CRC32)

OpenConsole()
PrintN("CRC32 Cecksum [hex] = "+UCase(b\$))
PrintN("CRC32 Cecksum [dec] = "+Val("\$"+b\$))
Input()

End```
Output:
```CRC32 Cecksum [hex] = 414FA339
CRC32 Cecksum [dec] = 1095738169```

## Python

### Library

`zlib.crc32` and `binascii.crc32` give identical results.

```>>> s = 'The quick brown fox jumps over the lazy dog'
>>> import zlib
>>> hex(zlib.crc32(s))
'0x414fa339'

>>> import binascii
>>> hex(binascii.crc32(s))
'0x414fa339'
```

If you have Python 2.x, these functions might return a negative integer; you would need to use `& 0xffffffff` to get the same answer as Python 3.x. With Python 3.x, convert first the string to bytes, for instance with `s.encode('UTF-8')`, as these functions do not accept strings.

### Implementation

#### Procedural

```def create_table():
a = []
for i in range(256):
k = i
for j in range(8):
if k & 1:
k ^= 0x1db710640
k >>= 1
a.append(k)
return a

def crc_update(buf, crc):
crc ^= 0xffffffff
for k in buf:
crc = (crc >> 8) ^ crc_table[(crc & 0xff) ^ k]
return crc ^ 0xffffffff

crc_table = create_table()
print(hex(crc_update(b"The quick brown fox jumps over the lazy dog", 0)))
```

#### Composition of pure functions

```'''CRC-32 checksums for ascii strings'''

from functools import (reduce)
from itertools import (islice)

# crc32 :: String -> Int
def crc32(s):
'''CRC-32 checksum for an ASCII encoded string'''
def go(x):
x2 = x >> 1
return 0xedb88320 ^ x2 if x & 1 else x2
table = [
index(iterate(go)(n))(8)
for n in range(0, 256)
]
return reduce(
lambda a, c: (a >> 8) ^ table[
(a ^ ord(c)) & 0xff
],
s,
(0xffffffff)
) ^ 0xffffffff

# ------------------------- TEST -------------------------
# main :: IO ()
def main():
'''Test'''
print(
format(
crc32('The quick brown fox jumps over the lazy dog'),
'02x'
)
)

# ----------------------- GENERIC ------------------------

# index (!!) :: [a] -> Int -> a
def index(xs):
'''Item at given (zero-based) index.'''
return lambda n: None if 0 > n else (
xs[n] if (
hasattr(xs, "__getitem__")
) else next(islice(xs, n, None))
)

# iterate :: (a -> a) -> a -> Gen [a]
def iterate(f):
'''An infinite list of repeated
applications of f to x.
'''
def go(x):
v = x
while True:
yield v
v = f(v)
return go

if __name__ == '__main__':
main()
```
Output:
`414fa339`

## QB64

Translation of: C
```PRINT HEX\$(crc32("The quick brown fox jumps over the lazy dog"))

FUNCTION crc32~& (buf AS STRING)
STATIC table(255) AS _UNSIGNED LONG
STATIC have_table AS _BYTE
DIM crc AS _UNSIGNED LONG, k AS _UNSIGNED LONG
DIM i AS LONG, j AS LONG

IF have_table = 0 THEN
FOR i = 0 TO 255
k = i
FOR j = 0 TO 7
IF (k AND 1) THEN
k = _SHR(k, 1)
k = k XOR &HEDB88320
ELSE
k = _SHR(k, 1)
END IF
table(i) = k
NEXT
NEXT
have_table = -1
END IF

crc = NOT crc ' crc = &Hffffffff

FOR i = 1 TO LEN(buf)
crc = (_SHR(crc, 8)) XOR table((crc AND &HFF) XOR ASC(buf, i))
NEXT

crc32~& = NOT crc
END FUNCTION```
Output:
`414FA339`

## Quackery

Translation of: Forth
```  [ table ]                      is crctable ( n --> n )

256 times
[ i^ 8 times
[ dup 1 >>
swap 1 & if
[ hex EDB88320 ^ ] ]
' crctable put ]

[ hex FFFFFFFF swap
witheach
[ over ^ hex FF &
crctable
swap 8 >> ^ ]
hex FFFFFFFF ^ ]            is crc-32   ( [ --> n )

\$ "The quick brown fox jumps over the lazy dog" crc-32
16 base put
echo
base release```
Output:
`414FA339`

## R

```digest("The quick brown fox jumps over the lazy dog","crc32", serialize=F)
```
Output:
`[1] "414fa339"`

## Racket

```#lang racket
(define (bytes-crc32 data)
(bitwise-xor
(for/fold ([accum #xFFFFFFFF])
([byte  (in-bytes data)])
(for/fold ([accum (bitwise-xor accum byte)])
([num (in-range 0 8)])
(bitwise-xor (quotient accum 2)
(* #xEDB88320 (bitwise-and accum 1)))))
#xFFFFFFFF))

(define (crc32 s)
(bytes-crc32 (string->bytes/utf-8 s)))

(format "~x" (crc32 "The quick brown fox jumps over the lazy dog"))
```
Output:
`"414fa339"`

## Raku

(formerly Perl 6)

### Call to native function crc32 in zlib

```use NativeCall;

sub crc32(int32 \$crc, Buf \$buf, int32 \$len --> int32) is native('z') { * }

my \$buf = 'The quick brown fox jumps over the lazy dog'.encode;
say crc32(0, \$buf, \$buf.bytes).fmt('%08x');
```

The libary name "z" resolves to /usr/lib/libz.so on a typical Linux system and /usr/lib/libz.dylib on Mac OS X, but may need to be changed for other platforms. Types may be platform-dependent as well. As written, the solution has been tested on Mac OS X 10.5.8 and Arch Linux 2016.08.01 x86_64.

Output:
`414fa339`

### Pure Raku

A fairly generic implementation with no regard to execution speed:

```sub crc(
Blob \$buf,
# polynomial including leading term, default: ISO 3309/PNG/gzip
:@poly = (1,0,0,0,0,0,1,0,0,1,1,0,0,0,0,0,1,0,0,0,1,1,1,0,1,1,0,1,1,0,1,1,1),
:\$n = @poly.end,      # degree of polynomial
:@init = 1 xx \$n,     # initial XOR bits
:@fini = 1 xx \$n,     # final XOR bits
:@bitorder = 0..7,    # default: eat bytes LSB-first
:@crcorder = 0..\$n-1, # default: MSB of checksum is coefficient of x⁰
) {
my @bit = flat (\$buf.list X+& (1 X+< @bitorder))».so».Int, 0 xx \$n;

@bit[0   .. \$n-1] «+^=» @init;
@bit[\$_  ..\$_+\$n] «+^=» @poly if @bit[\$_] for 0..@bit.end-\$n;
@bit[*-\$n..  *-1] «+^=» @fini;

:2[@bit[@bit.end X- @crcorder]];
}

say crc('The quick brown fox jumps over the lazy dog'.encode('ascii')).base(16);
```
Output:
`414FA339`

## REXX

```/*REXX program computes the  CRC─32  (32 bit Cyclic Redundancy Check)  checksum  for a  */
/*─────────────────────────────────given string  [as described in ISO 3309, ITU─T V.42].*/
call show  'The quick brown fox jumps over the lazy dog'               /*the 1st string.*/
call show  'Generate CRC32 Checksum For Byte Array Example'            /* "  2nd    "   */
exit                                             /*stick a fork in it,  we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
CRC_32: procedure; parse arg !,\$; c= 'edb88320'x /*2nd arg used for repeated invocations*/
f= 'ffFFffFF'x /* [↓]  build an  8─bit  indexed table,*/
do i=0  for 256;        z= d2c(i)      /*                  one byte at a time.*/
r= right(z, 4, '0'x)                   /*insure the  "R"   is thirty─two bits.*/
/* [↓]  handle each rightmost byte bit.*/
do j=0  for 8;       rb= x2b(c2x(r)) /*handle each bit of rightmost 8 bits. */
r= x2c( b2x(0 || left(rb, 31) ) )    /*shift it right (an unsigned)  1  bit.*/
if right(rb,1)  then r= bitxor(r, c) /*this is a bin bit for XOR grunt─work.*/
end    /*j*/
!.z= r                                 /*assign to an eight─bit index table.  */
end      /*i*/
\$=bitxor( word(\$ '0000000'x, 1), f)      /*utilize the user's CRC or a default. */
do k=1  for length(!  )                /*start number crunching the input data*/
?= bitxor(right(\$,1),  substr(!,k,1) )
\$= bitxor('0'x || left(\$, 3),  !.?)
end   /*k*/
return \$                                 /*return with cyclic redundancy check. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
show:   procedure;   parse arg Xstring;   numeric digits 12;      say;     say
checksum= bitxor(CRC_32(Xstring), 'ffFFffFF'x) /*invoke CRC_32 to create a CRC. */
say center(' input string [length of' length(Xstring) "bytes] ", 79, '═')
say Xstring;      say                          /*show the string on its own line*/
say  "hex CRC─32 checksum ="   c2x(checksum)     left('', 15),
"dec CRC─32 checksum ="   c2d(checksum)   /*show the CRC─32 in hex and dec.*/
return
```
output   when using the internal default input:
```══════════════════════ input string [length of 43 bytes] ══════════════════════
The quick brown fox jumps over the lazy dog

hex CRC-32 checksum = 414FA339                 dec CRC-32 checksum = 1095738169

══════════════════════ input string [length of 46 bytes] ══════════════════════
Generate CRC32 Checksum For Byte Array Example

hex CRC-32 checksum = D1370232                 dec CRC-32 checksum = 3510043186
```

## RPL

Translation of: FreeBASIC
```≪ → string
≪ 32 STWS                     @ set binary word size to 32
IFERR ‘CRCtable’ RCL THEN
{ }
0 255 FOR j
j R→B
0 7 START
SR IF LAST #1 AND B→R THEN #EDB88320h XOR END
NEXT + NEXT
‘CRCtable’ STO
END
DROP #0 NOT
1 string SIZE FOR j
SRB SWAP
#FFh AND string j DUP SUB NUM R→B XOR
B→R 1 + ‘CRCtable’ SWAP GET XOR
NEXT
NOT
≫ ≫ ‘CRC32’ STO
```
```"The quick brown fox jumps over the lazy dog" CRC32
```
Output:
```1: # 414FA339h
```

## Ruby

Use 'zlib' from standard library.

```require 'zlib'
printf "0x%08x\n", Zlib.crc32('The quick brown fox jumps over the lazy dog')
# => 0x414fa339
```

Reimplement CRC-32 in Ruby, with comments to show the polynomials.

```module CRC
# Divisor is a polynomial of degree 32 with coefficients modulo 2.
# We store Divisor in a 33-bit Integer; the polynomial is
#   Divisor[32] + Divisor[31] * x + ... + Divisor[0] * x**32
Divisor = [0, 1, 2, 4, 5, 7, 8, 10, 11, 12, 16, 22, 23, 26, 32] \
.inject(0) {|sum, exponent| sum + (1 << (32 - exponent))}

# This table gives the crc (without conditioning) of every possible
# _octet_ from 0 to 255. Each _octet_ is a polynomial of degree 7,
#   octet[7] + octet[6] * x + ... + octet[0] * x**7
# Then remainder = Table[octet] is the remainder from
# _octet_ times x**32 divided by Divisor,
#   remainder[31] + remainder[30] + ... + remainder[0] * x**31
Table = Array.new(256) do |octet|
# Find remainder from polynomial long division.
#    octet[ 7] * x**32 + ... +   octet[0] * x**39
#  Divisor[32] * x**0  + ... + Divisor[0] * x**32
remainder = octet
(0..7).each do |i|
# Find next term of quotient. To simplify the code,
# we assume that Divisor[0] is 1, and we only check
# remainder[i]. We save remainder, forget quotient.
if remainder[i].zero?
# Next term of quotient is 0 * x**(7 - i).
# No change to remainder.
else
# Next term of quotient is 1 * x**(7 - i). Multiply
# this term by Divisor, then subtract from remainder.
#  * Multiplication uses left shift :<< to align
#    the x**(39 - i) terms.
#  * Subtraction uses bitwise exclusive-or :^.
remainder ^= (Divisor << i)
end
end
remainder >> 8      # Remove x**32 to x**39 terms.
end

module_function

def crc32(string, crc = 0)
# Pre-conditioning: Flip all 32 bits. Without this step, a string
# preprended with extra "\0" would have same crc32 value.
crc ^= 0xffff_ffff

# Iterate octets to perform polynomial long division.
string.each_byte do |octet|

# Update _crc_ by continuing its polynomial long division.
# Our current remainder is old _crc_ times x**8, plus
# new _octet_ times x**32, which is
#   crc[32] * x**8 + crc[31] * x**9 + ... + crc[8] * x**31 \
#     + (crc[7] + octet[7]) * x**32 + ... \
#     + (crc[0] + octet[0]) * x**39
#
# Our new _crc_ is the remainder from this polynomial divided by
# Divisor. We split the terms into part 1 for x**8 to x**31, and
# part 2 for x**32 to x**39, and divide each part separately.
# Then remainder 1 is trivial, and remainder 2 is in our Table.

remainder_1 = crc >> 8
remainder_2 = Table[(crc & 0xff) ^ octet]

# Our new _crc_ is sum of both remainders. (This sum never
# overflows to x**32, so is not too big for Divisor.)
crc = remainder_1 ^ remainder_2
end

# Post-conditioning: Flip all 32 bits. If we later update _crc_,
# this step cancels the next pre-conditioning.
crc ^ 0xffff_ffff
end
end

printf "0x%08x\n", CRC.crc32("The quick brown fox jumps over the lazy dog")
# => 0x414fa339
```

## Rust

This does not perform any caching of the lookup table for simplicity.

```fn crc32_compute_table() -> [u32; 256] {
let mut crc32_table = [0; 256];

for n in 0..256 {
crc32_table[n as usize] = (0..8).fold(n as u32, |acc, _| {
match acc & 1 {
1 => 0xedb88320 ^ (acc >> 1),
_ => acc >> 1,
}
});
}

crc32_table
}

fn crc32(buf: &str) -> u32 {
let crc_table = crc32_compute_table();

!buf.bytes().fold(!0, |acc, octet| {
(acc >> 8) ^ crc_table[((acc & 0xff) ^ octet as u32) as usize]
})
}

fn main() {
println!("{:x}", crc32("The quick brown fox jumps over the lazy dog"));
}
```
Output:
```414fa339
```

## Scala

Translation of: Java
```import java.util.zip.CRC32
val crc=new CRC32
crc.update("The quick brown fox jumps over the lazy dog".getBytes)
println(crc.getValue.toHexString)  //> 414fa339
```

## Seed7

```\$ include "seed7_05.s7i";
include "crc32.s7i";

const proc: main is func
begin
writeln(ord(crc32("The quick brown fox jumps over the lazy dog")) radix 16 lpad0 8);
end func;```
Output:
```414fa339
```

## Shell

### Bash

```#!/usr/bin/env bash
declare -i -a CRC32_LOOKUP_TABLE

__generate_crc_lookup_table() {
local -i -r LSB_CRC32_POLY=0xEDB88320 # The CRC32 polynomal LSB order
local -i index byte lsb
for index in {0..255}; do
((byte = 255 - index))
for _ in {0..7}; do # 8-bit lsb shift
((lsb = byte & 0x01, byte = ((byte >> 1) & 0x7FFFFFFF) ^ (lsb == 0 ? LSB_CRC32_POLY : 0)))
done
((CRC32_LOOKUP_TABLE[index] = byte))
done
}
__generate_crc_lookup_table
typeset -r CRC32_LOOKUP_TABLE

crc32_string() {
[[ \${#} -eq 1 ]] || return
local -i i byte crc=0xFFFFFFFF index
for ((i = 0; i < \${#1}; i++)); do
byte=\$(printf '%d' "'\${1:i:1}") # Get byte value of character at i
((index = (crc ^ byte) & 0xFF, crc = (CRC32_LOOKUP_TABLE[index] ^ (crc >> 8)) & 0xFFFFFFFF))
done
echo \$((crc ^ 0xFFFFFFFF))
}

printf 'The CRC32 of: %s\nis: 0x%08x\n' "\${1}" "\$(crc32_string "\${1}")"

# crc32_string "The quick brown fox jumps over the lazy dog"
# yields 414fa339
```

### POSIX

The POSIX Shell has no array type and no string indexation. It costs less to recompute polynomal shift for each character than indexing with external tools like `awk` or `tr`.

```#!/usr/bin/env sh
# POSIX Shell CRC32 of string
# @Name: crc32.sh
# @Version: 1.0.1
# @Author: Léa Gris <lea.gris@noiraude.net>
# @Date: Wed, 27 Mar 2019

# POSIX Shell has no array or string index
# Implementing a pre-computed CRC32 byte indexed look-up table
# would cost more CPU cycles calling external tools like
# awk or tr to index records from a string.

# Computes the CRC32 of the input data stream
# <&1: The input data stream
# >&1: The CRC32 integer of the input data stream
crc32_stream() {
crc=0xFFFFFFFF # The Initial CRC32 value
p=0xedb88320   # The CRC32 polynomial
r=0            # The polynomial reminder
c=''           # The current character
byte=0         # The byte value of the current character
# Iterates each character of the input stream
while c="\$(dd bs=1 count=1 2>/dev/null)" && [ -n "\$c" ]; do
byte=\$(printf '%d' "'\$c")  # Converts the character into its byte value
r=\$(((crc & 0xff) ^ byte)) # XOR LSB of CRC with current byte
# 8-bit lsb shift with XOR polynomial reminder when odd
for _ in _ _ _ _ _ _ _ _; do
t=\$((r >> 1))
r=\$(((r & 1) ? t ^ p : t))
done
crc=\$(((crc >> 8) ^ r)) # XOR MSB of CRC with Reminder
done

# Output CRC32 integer XOR mask 32 bits
echo \$((crc ^ 0xFFFFFFFF))
}

# Computes the CRC32 of the argument string
# 1: The argument string
# >&1: The CRC32 integer of the argument string
crc32_string() {
[ \$# -eq 1 ] || return # argument required
# Streams with printf to prevent suffixing the string
# with a newline, since echo -n is not available in POSIX Shell
printf '%s' "\$1" | crc32_stream
}

printf 'The CRC32 of: %s\nis: %08x\n' "\$1" "\$(crc32_string "\$1")"

# crc32_string "The quick brown fox jumps over the lazy dog"
# yields 414fa339
```
Output:
```bash ./crc32.sh "The quick brown fox jumps over the lazy dog"
The CRC32 of: The quick brown fox jumps over the lazy dog
is: 0x414fa339```

## Smalltalk

Works with: Smalltalk/X

the CRC32Stream utility class can do it for me:

```CRC32Stream hashValueOf:'The quick brown fox jumps over the lazy dog'
```
Output:
```1095738169 "which is 16r414FA339"
```

## Swift

Using the zlib crc32 function available to Swift from libz.dylib.

```import Foundation

let strData = "The quick brown fox jumps over the lazy dog".dataUsingEncoding(NSUTF8StringEncoding,
allowLossyConversion: false)
let crc = crc32(uLong(0), UnsafePointer<Bytef>(strData!.bytes), uInt(strData!.length))

println(NSString(format:"%2X", crc))
```
Output:
```414FA339
```

## Tcl

```package require Tcl 8.6

set data "The quick brown fox jumps over the lazy dog"
puts [format "%x" [zlib crc32 \$data]]
```
Output:
`414fa339`

Alternatively, with older versions of Tcl:

Library: Tcllib (Package: crc32)
```package require crc32
puts [format "%x" [crc::crc32 \$data]]
```

With the same input data, it produces identical output.

## TXR

### Standard Library

`(crc32 "The quick brown fox jumps over the lazy dog")`
Output:
`1095738169`

```(with-dyn-lib "libz.so.1"
(deffi zlib-crc32 "crc32" ulong (ulong str uint)))```
Output:
```\$ txr -i crc32-zlib.tl
1> (let ((s "The quick brown fox jumps over the lazy dog"))
(zlib-crc32 0 s (coded-length s)))
1095738169```

Note: `coded-length` gives UTF-8 length; `len` yields a code point count. Since this is an ASCII string, the two agree.

### Lisp Code

```(defvarl crc-tab
#(#x00000000 #x77073096 #xee0e612c #x990951ba #x076dc419 #x706af48f
#xe963a535 #x9e6495a3 #x0edb8832 #x79dcb8a4 #xe0d5e91e #x97d2d988
#x09b64c2b #x7eb17cbd #xe7b82d07 #x90bf1d91 #x1db71064 #x6ab020f2
#x136c9856 #x646ba8c0 #xfd62f97a #x8a65c9ec #x14015c4f #x63066cd9
#xfa0f3d63 #x8d080df5 #x3b6e20c8 #x4c69105e #xd56041e4 #xa2677172
#x3c03e4d1 #x4b04d447 #xd20d85fd #xa50ab56b #x35b5a8fa #x42b2986c
#xdbbbc9d6 #xacbcf940 #x32d86ce3 #x45df5c75 #xdcd60dcf #xabd13d59
#x26d930ac #x51de003a #xc8d75180 #xbfd06116 #x21b4f4b5 #x56b3c423
#xcfba9599 #xb8bda50f #x2802b89e #x5f058808 #xc60cd9b2 #xb10be924
#x2f6f7c87 #x58684c11 #xc1611dab #xb6662d3d #x76dc4190 #x01db7106
#x98d220bc #xefd5102a #x71b18589 #x06b6b51f #x9fbfe4a5 #xe8b8d433
#x7807c9a2 #x0f00f934 #x9609a88e #xe10e9818 #x7f6a0dbb #x086d3d2d
#x91646c97 #xe6635c01 #x6b6b51f4 #x1c6c6162 #x856530d8 #xf262004e
#x6c0695ed #x1b01a57b #x8208f4c1 #xf50fc457 #x65b0d9c6 #x12b7e950
#x8bbeb8ea #xfcb9887c #x62dd1ddf #x15da2d49 #x8cd37cf3 #xfbd44c65
#x4db26158 #x3ab551ce #xa3bc0074 #xd4bb30e2 #x4adfa541 #x3dd895d7
#xa4d1c46d #xd3d6f4fb #x4369e96a #x346ed9fc #xad678846 #xda60b8d0
#x44042d73 #x33031de5 #xaa0a4c5f #xdd0d7cc9 #x5005713c #x270241aa
#xbe0b1010 #xc90c2086 #x5768b525 #x206f85b3 #xb966d409 #xce61e49f
#x5edef90e #x29d9c998 #xb0d09822 #xc7d7a8b4 #x59b33d17 #x2eb40d81
#xb7bd5c3b #xc0ba6cad #xedb88320 #x9abfb3b6 #x03b6e20c #x74b1d29a
#xead54739 #x9dd277af #x04db2615 #x73dc1683 #xe3630b12 #x94643b84
#x0d6d6a3e #x7a6a5aa8 #xe40ecf0b #x9309ff9d #x0a00ae27 #x7d079eb1
#xf00f9344 #x8708a3d2 #x1e01f268 #x6906c2fe #xf762575d #x806567cb
#x196c3671 #x6e6b06e7 #xfed41b76 #x89d32be0 #x10da7a5a #x67dd4acc
#xf9b9df6f #x8ebeeff9 #x17b7be43 #x60b08ed5 #xd6d6a3e8 #xa1d1937e
#x38d8c2c4 #x4fdff252 #xd1bb67f1 #xa6bc5767 #x3fb506dd #x48b2364b
#xd80d2bda #xaf0a1b4c #x36034af6 #x41047a60 #xdf60efc3 #xa867df55
#x316e8eef #x4669be79 #xcb61b38c #xbc66831a #x256fd2a0 #x5268e236
#xcc0c7795 #xbb0b4703 #x220216b9 #x5505262f #xc5ba3bbe #xb2bd0b28
#x2bb45a92 #x5cb36a04 #xc2d7ffa7 #xb5d0cf31 #x2cd99e8b #x5bdeae1d
#x9b64c2b0 #xec63f226 #x756aa39c #x026d930a #x9c0906a9 #xeb0e363f
#x72076785 #x05005713 #x95bf4a82 #xe2b87a14 #x7bb12bae #x0cb61b38
#x92d28e9b #xe5d5be0d #x7cdcefb7 #x0bdbdf21 #x86d3d2d4 #xf1d4e242
#x68ddb3f8 #x1fda836e #x81be16cd #xf6b9265b #x6fb077e1 #x18b74777
#x88085ae6 #xff0f6a70 #x66063bca #x11010b5c #x8f659eff #xf862ae69
#x616bffd3 #x166ccf45 #xa00ae278 #xd70dd2ee #x4e048354 #x3903b3c2
#xa7672661 #xd06016f7 #x4969474d #x3e6e77db #xaed16a4a #xd9d65adc
#x40df0b66 #x37d83bf0 #xa9bcae53 #xdebb9ec5 #x47b2cf7f #x30b5ffe9
#xbdbdf21c #xcabac28a #x53b39330 #x24b4a3a6 #xbad03605 #xcdd70693
#x54de5729 #x23d967bf #xb3667a2e #xc4614ab8 #x5d681b02 #x2a6f2b94
#xb40bbe37 #xc30c8ea1 #x5a05df1b #x2d02ef8d))

(defun crc32 (buf)
(let ((crc #xffffffff)
(l (len buf)))
(each ((i 0..l))
(set crc (logxor [crc-tab (logand (logxor crc [buf i]) #xff)]
(ash crc -8))))
(logxor crc #xffffffff)))```
Output:
```\$ ./txr -i crc.tl
warning: (crc.tl:46) defun: redefining crc32, which is a built-in defun
1> (crc32 (buf-str "The quick brown fox jumps over the lazy dog"))
1095738169```

## Vala

### Library

```using ZLib.Utility;

void main() {
var str = (uint8[])"The quick brown fox jumps over the lazy dog".to_utf8();
stdout.printf("%lx\n", crc32(0, str));
}
```
Output:
```414fa339
```

### Implementation

```public class Crc32
{
private const uint32 s_generator = 0xedb88320u;

public Crc32()
{
m_table = new uint32[256];
uint32 rem;
for (uint32 i = 0; i < 256; i++) {
rem = i;
for (uint32 j = 0; j < 8; j++) {
if ((rem & 1) != 0) {
rem >>= 1;
rem ^= s_generator;
} else
rem >>= 1;
}
m_table[i] = rem;
}
}

public uint32 get(string str) {
uint32 crc = 0;
crc = ~crc;
for (int i = 0; i < str.length; i++) {
crc = (crc >> 8) ^ m_table[(crc & 0xff) ^ str[i]];
}
return ~crc;
}

private uint32[] m_table;
}

void main() {
var crc32 = new Crc32();
stdout.printf("%x\n", crc32.get("The quick brown fox jumps over the lazy dog"));
}
```
Output:
```414fa339
```

## VAX Assembly

```                           EDB88320  0000     1 poly:   .long   ^xedb88320                      ;crc32
00000044  0004     2 table:  .blkl   16
0044     3
4C 58 21 0000004C'010E0000' 0044     4 fmt:    .ascid  "!XL"                           ;result format
36 35 34 33 32 31 00000057'010E0000' 004F     5 result: .ascid  "12345678"                      ; and buffer
38 37  005D
0000  005F     6 .entry  crc,0
A0 AF   7F  0061     7         pushaq  table                           ;fill table
99 AF   DF  0064     8         pushal  poly                            ; for
00000000'GF   02   FB  0067     9         calls   #2, g^lib\$crc_table             ;  crc opcode
2B'  FFFFFFFF 8F   93 AF   0B  006E    10         crc     table, #-1, s^#len, b^msg       ;table,init,len,string
98'AF       0077
50   50   D2  0079    11         mcoml   r0, r0                          ;invert result
007C    12         \$fao_s	ctrstr = fmt, outbuf = result, p1 = r0 ; format
BF AF   7F  008D    13 	pushaq	result				;and show
00000000'GF   01   FB  0090    14         calls   #1, g^lib\$put_output            ;  result 414fa339
04  0097    15         ret
0098    16
72 62 20 6B 63 69 75 71 20 65 68 54  0098    17 msg:    .ascii  "The quick brown fox jumps over the lazy dog"
70 6D 75 6A 20 78 6F 66 20 6E 77 6F  00A4
6C 20 65 68 74 20 72 65 76 6F 20 73  00B0
67 6F 64 20 79 7A 61  00BC
0000002B  00C3    18 len = .-msg
00C3    19 .end	crc```

## VBScript

VBScript does'nt have bit rotation instructions and then bit to bit logic converts the default Double values to SIGNED 32 bit integers and back. A table driven implementation is required to speed things up. The code generates the table on the fly.

```dim crctbl(255)
const crcc =&hEDB88320

sub gencrctable
for i= 0 to 255
k=i
for j=1 to 8
if k and 1 then
k=(k and &h7fffffff)\2 or (&h40000000 and ((k and &h80000000)<>0))
k=k xor crcc
else
k=(k and &h7fffffff)\2 or (&h40000000 and ((k and &h80000000)<>0))
end if
next ' j
crctbl(i)=k
next
end sub

function crc32 (buf)
dim r,r1,i
r=&hffffffff
for i=1 to len(buf)
r1=(r and &h7fffffff)\&h100 or (&h800000 and (r and &h80000000)<>0)
r=r1 xor crctbl((asc(mid(buf,i,1))xor r) and 255)
next
crc32=r xor &hffffffff
end function

'414FA339
gencrctable
wscript.stdout.writeline hex(crc32("The quick brown fox jumps over the lazy dog"))```

Output

```414FA339
```

## Visual Basic

Works with: Visual Basic version 5
Works with: Visual Basic version 6
Works with: VBA version Access 97
Works with: VBA version 6.5
Works with: VBA version 7.1
Library: Win32

Not an ideal task for Visual Basic because the language lacks bit shifting operators (which can of course be emulated, but that's slow). Then again, since the only platform supported by VB is Microsoft Windows (32 Bit Subsystem), we can let the Windows API do the work for us. RtlComputeCrc32() was available since Windows XP and is still present in Windows 10.

```Option Explicit
Declare Function RtlComputeCrc32 Lib "ntdll.dll" _
(ByVal dwInitial As Long, pData As Any, ByVal iLen As Long) As Long
'--------------------------------------------------------------------
Sub Main()
Dim s As String
Dim b() As Byte
Dim l As Long

s = "The quick brown fox jumps over the lazy dog"
b() = StrConv(s, vbFromUnicode) 'convert Unicode to ASCII
l = RtlComputeCrc32(0&, b(0), Len(s))
Debug.Assert l = &H414FA339

End Sub```

## Visual Basic .NET

Allows the resumption of calculations, useful for processing a large file with a series of buffer reads.

```Public Class Crc32

' Table for pre-calculated values.
Shared table(255) As UInteger

' Initialize table
Shared Sub New()
For i As UInteger = 0 To table.Length - 1
Dim te As UInteger = i ' table entry
For j As Integer = 0 To 7
If (te And 1) = 1 Then te = (te >> 1) Xor &HEDB88320UI Else te >>= 1
Next
table(i) = te
Next
End Sub

' Return checksum calculation for Byte Array,
'  optionally resuming (used when breaking a large file into read-buffer-sized blocks).
' Call with Init = False to continue calculation.
Public Shared Function cs(BA As Byte(), Optional Init As Boolean = True) As UInteger
Static crc As UInteger
If Init Then crc = UInteger.MaxValue
For Each b In BA
crc = (crc >> 8) Xor table((crc And &HFF) Xor b)
Next
Return Not crc
End Function

End Class
```

Test:

```    ' Returns a Byte Array from a string of ASCII characters.
Function Str2BA(Str As String) As Byte()
Return System.Text.Encoding.ASCII.GetBytes(Str)
End Function

' Returns a Hex string from an UInteger, formatted to a number of digits,
Function HexF(Value As UInteger, Digits As Integer) As String
HexF = Hex(Value)
If Len(HexF) < Digits Then HexF = StrDup(Digits - Len(HexF), "0") & HexF
End Function

' Tests Crc32 class
Sub Test()
Dim Str As String = "The quick brown fox jumps over the lazy dog"
Debug.Print("Input = """ & Str & """")
' Convert string to Byte Array, compute crc32, and display formatted result
Debug.Print("Crc32 = " & HexF(Crc32.cs(Str2BA(Str)), 8))
' This next code demonstrates continuing a crc32 calculation when breaking the input
' into pieces, such as processing a large file by a series of buffer reads.
Crc32.cs(Str2BA(Mid(Str, 1, 20)))
Debug.Print("Crc32 = " & HexF(Crc32.cs(Str2BA(Mid(Str, 21)), False), 8))
End Sub
```

Output:

```Input = "The quick brown fox jumps over the lazy dog"
Crc32 = 414FA339
Crc32 = 414FA339
```

## V (Vlang)

```import hash.crc32

fn main() {
text := "The quick brown fox jumps over the lazy dog"
result := crc32.sum(text.bytes())
println(result.hex())
}```
Output:
```414fa339
```

## Wren

Translation of: Go
Library: Wren-fmt
```import "./fmt" for Conv

class CRC32 {
static init() {
__table = List.filled(256, 0)
for (i in 0..255) {
var word = i
for (j in 0..7) {
if (word&1 == 1) {
word = (word >> 1) ^ 0xedb88320
} else {
word = word >> 1
}
}
__table[i] = word
}
}

static compute(s) {
var crc = ~0
var le = s.bytes.count
for (i in 0...le) {
var crb = crc & 0xff
crc = __table[crb^s[i].bytes[0]] ^ (crc >> 8)
}
return ~crc
}
}

CRC32.init()
var crc = CRC32.compute("The quick brown fox jumps over the lazy dog")
System.print(Conv.hex(crc))
```
Output:
```414fa339
```

## XPL0

```code HexOut=27;         \intrinsic routine
string 0;               \use zero-terminated strings

func CRC32(Str, Len);   \Return CRC-32 for given string
char Str;  int Len;     \byte array, number of bytes
int  I, J, R, C;
[R:= -1;                \initialize with all 1's
for J:= 0 to Len-1 do
[C:= Str(J);
for I:= 0 to 8-1 do \for each bit in byte...
[if (R xor C) and 1 then R:= R>>1 xor \$EDB88320
else R:= R>>1;
C:= C>>1;
];
];
return not R;
];

HexOut(0, CRC32("The quick brown fox jumps over the lazy dog", 43))```
Output:
```414FA339
```

## zkl

Using zlib:

```var [const] ZLib=Import("zeelib");
ZLib.calcCRC32(Data(Void,"The quick brown fox jumps over the lazy dog"));
//-->0x414fa339```

## Zig

```const std = @import("std");
const Crc32Ieee = std.hash.Crc32;

pub fn main() !void {
var res: u32 = Crc32Ieee.hash("The quick brown fox jumps over the lazy dog");
std.debug.print("{x}\n", .{res});
}
```
Output:
```414fa339
```