String Byte Length
In this task, the goal is to find the byte length of a string. This means encodings like UTF-8 may need to be handled specially, as there is not necessarily a one-to-one relationship between bytes and characters, and some languages recognize this. For example, the character length of "møøse" is 5 but the byte length is 7 in UTF-8 and 10 in UTF-16.
You are encouraged to solve this task according to the task description, using any language you may know.
For character length, see String Character Length.
4D
$length:=Length("Hello, world!")
Ada
Compiler: GCC 4.1.2
Str : String := "Hello World"; Length : constant Natural := Str'Size / System.Storage_Unit;
The 'size attribute returns the size of an object in bits. System.Storage_Unit is the number of bits in a byte on the current machine.
AppleScript
count of "Hello World"
AWK
From within any code block:
w=length("Hello, world!") # static string example
x=length("Hello," s " world!") # dynamic string example
y=length($1) # input field example
z=length(s) # variable name example
Ad hoc program from command line:
echo "Hello, wørld!" | awk '{print length($0)}' # 14
From executable script: (prints for every line arriving on stdin)
#!/usr/bin/awk -f
{print"The length of this line is "length($0)}
C
Compiler: GCC 3.3.3
#include <string.h>
int main(void)
{
const char *string = "Hello, world!";
size_t length = strlen(string);
return 0;
}
or by hand:
int main(void)
{
const char *string = "Hello, world!";
size_t length = 0;
char *p = (char *) string;
while (*p++ != '\0') length++;
return 0;
}
or (for arrays of char only)
#include <stdlib.h>
int main(void)
{
char const s[] = "Hello, world!";
size_t length = sizeof s - 1;
return 0;
}
C++
Standard: ISO C++ (AKA C++98):
Compiler: g++ 4.0.2
#include <string> // note: not <string.h>
int main()
{
std::string s = "Hello, world!";
std::string::size_type length = s.length(); // option 1: In Characters/Bytes
std::string::size_type size = s.size(); // option 2: In Characters/Bytes
// In bytes same as above since sizeof(char) == 1
std::string::size_type bytes = s.length() * sizeof(std::string::value_type);
}
For wide character strings:
#include <string>
int main()
{
std::wstring s = L"\u304A\u306F\u3088\u3046";
std::wstring::size_type length = s.length() * sizeof(std::wstring::value_type); // in bytes
}
C#
Platform: .NET Language Version: 1.0+
string s = "Hello, world!"; int blength = System.Text.Encoding.GetBytes(s).length; // In Bytes.
Clean
Clean Strings are unboxed arrays of characters. Characters are always a single byte. The function size returns the number of elements in an array.
import StdEnv strlen :: String -> Int strlen string = size string Start = strlen "Hello, world!"
ColdFusion
#len("Hello World")#
Common Lisp
(length "Hello World")
Component Pascal
LEN("Hello, World!")
Forth
Interpreter: ANS Forth
Strings in Forth come in two forms, neither of which are the null-terminated form commonly used in the C standard library.
Counted string
A counted string is a single pointer to a short string in memory. The string's first byte is the count of the number of characters in the string. This is how symbols are stored in a Forth dictionary.
CREATE s ," Hello world" \ create string "s" s C@ ( -- length=11 )
Stack string
A string on the stack is represented by a pair of cells: the address of the string data and the length of the string data (in characters). The word COUNT converts a counted string into a stack string. The STRING utility wordset of ANS Forth works on these addr-len pairs. This representation has the advantages of not requiring null-termination, easy representation of substrings, and not being limited to 255 characters.
S" string" ( addr len) DUP . \ 6
Haskell
It is not possible to determine the "byte length" of an ordinary string, because in Haskell, a string is a boxed list of unicode characters. So each character in a string is represented as whatever the compiler considers as the most efficient representation of a cons-cell and a unicode character, and not as a byte.
For efficient storage of sequences of bytes, there's Data.ByteString, which uses Word8 as a base type. Byte strings have an additional Data.ByteString.Char8 interface, which will truncate each Unicode Char to 8 bits as soon as it is converted to a byte string. However, this is not adequate for the task, because truncation simple will garble characters other than Latin-1, instead of encoding them into UTF-8, say.
There are several (non-standard, so far) Unicode encoding libraries available on Hackage. As an example, we'll use encoding-0.2, as Data.Encoding:
import Data.Encoding import Data.ByteString as B strUTF8 :: ByteString strUTF8 = encode UTF8 "Hello World!" strUTF32 :: ByteString strUTF32 = encode UTF32 "Hello World!" strlenUTF8 = B.length strUTF8 strlenUTF32 = B.length strUTF32
IDL
Compiler: any IDL compiler should do
length = strlen("Hello, world!")
Java
Java encodes strings in UTF-16, which represents each character with one or two 16-bit values. The length method of String objects returns the number of 16-bit values used to encode a string, so the number of bytes can be determined by doubling that number.
String s = "Hello, world!"; int byteCount = s.length() * 2;
Another way to know the byte length of a string is to explicitly specify the charset we desire.
String s = "Hello, world!";
int byteCountUTF16 = s.getBytes("UTF-16").length;
int byteCountUTF8 = s.getBytes("UTF-8").length;
JavaScript
JavaScript encodes strings in UTF-16, which represents each character with one or two 16-bit values. The length property of string objects gives the number of 16-bit values used to encode a string, so the number of bytes can be determined by doubling that number.
var s = "Hello, world!"; var byteCount = s.length * 2; //26
JudoScript
//Store length of hello world in length and print it . length = "Hello World".length();
LSE64
LSE stores strings as arrays of characters in 64-bit cells plus a count.
" Hello world" @ 1 + 8 * , # 96 = (11+1)*(size of a cell) = 12*8
Lua
Interpreter: Lua 5.0 or later.
string="Hello world" length=#string
mIRC Scripting Language
alias stringlength { echo -a Your Name is: $len($$?="Whats your name") letters long! }
OCaml
Interpreter/Compiler: Ocaml 3.09
String.length "Hello world";;
Perl
Interpreter: perl 5.8
Strings in Perl consist of characters. Measuring the byte length therefore requires conversion to some binary representation (called encoding, both noun and verb).
use utf8; # so we can use literal characters like ☺ in source use Encode qw(encode); print length encode 'UTF-8', "Hello, world! ☺"; # 17. The last character takes 3 bytes, the others 1 byte each. print length encode 'UTF-16', "Hello, world! ☺"; # 32. 2 bytes for the BOM, then 15 byte pairs for each character.
PHP
$length = strlen('Hello, world!');
PL/SQL
DECLARE string VARCHAR2( 50 ) := 'Hello, world!'; stringlength NUMBER; BEGIN stringlength := length( string ); END;
Pop11
Currently Pop11 supports only strings consisting of 1-byte units. Strings can carry arbitrary binary data, so user can for example use UTF-8 (however builtin procedures will treat each byte as a single character). The length function for strings returns length in bytes:
lvars str = 'Hello, world!'; lvars len = length(str);
Python
Interpreter: Python 2.x
Byte length depends on the encoding. Python use 2 or 4 bytes per character internally for unicode strings, depending on how it was built. The internal representation is not interesting for the user.
# The letter Alef
>>> len(u'\u05d0'.encode('utf-8'))
2
>>> len(u'\u05d0'.encode('iso-8859-8'))
1
Example from the problem statement:
#!/bin/env python
# -*- coding: UTF-8 -*-
s = u"møøse"
assert len(s) == 5
assert len(s.encode('UTF-8')) == 7
assert len(s.encode('UTF-16')) == 12 #XXX it should be `10' as problem statement says
Ruby
string="Hello world" print string.length
or
puts "Hello World".length
Scheme
(string-length "Hello world")
Smalltalk
string := 'Hello, world!". string size.
Standard ML
Interpreter: SML/NJ 110.60, Moscow ML 2.01 (January 2004)
Compiler: MLton 20061107
val strlen = size "Hello, world!";
Tcl
Basic version:
string bytelength "Hello, world!"
or more elaborately, needs Interpreter any 8.X. Tested on 8.4.12.
fconfigure stdout -encoding utf-8; #So that Unicode string will print correctly set s1 "hello, world" set s2 "\u304A\u306F\u3088\u3046" puts [format "length of \"%s\" in bytes is %d" $s1 [string bytelength $s1]] puts [format "length of \"%s\" in bytes is %d" $s2 [string bytelength $s2]]
Toka
" hello, world!" string.getLength
UNIX Shell
With external utilities:
Interpreter: any bourne shell
string='Hello, world!' length=`echo -n "$string" | wc -c | tr -dc '0-9'` echo $length # if you want it printed to the terminal
With SUSv3 parameter expansion modifier:
Interpreter: Almquist SHell (NetBSD 3.0), Bourne Again SHell 3.2, Korn SHell (5.2.14 99/07/13.2), Z SHell
string='Hello, world!'
length="${#string}"
echo $length # if you want it printed to the terminal
VBScript
LenB(string|varname)
Returns the number of bytes required to store a string in memory Returns null if string|varname is null
xTalk
Interpreter: HyperCard
put the length of "Hello World"
or
put the number of characters in "Hello World"