Literals/Integer
You are encouraged to solve this task according to the task description, using any language you may know.
Some programming languages have ways of expressing integer literals in bases other than the normal base ten.
Show how integer literals can be expressed in as many bases as your language allows.
Note: this should not involve the calling of any functions/methods but should be interpreted by the compiler or interpreter as an integer written to a given base.
Also show any other ways of expressing literals, e.g. for different types of integers.
Ada
In Ada integer literals may have the form <base>#<numeral>#. Here <base> can be from the range 2..16. For example: <lang ada> with Ada.Integer_Text_IO; use Ada.Integer_Text_IO;
procedure Test_Literals is begin
Put (16#2D7#); Put (10#727#); Put (8#1_327#); Put (2#10_1101_0111#);
end Test_Literals; </lang> Sample output:
727 727 727 727
AWK
<lang>BEGIN {
if ( (0x2d7 == 727) &&
(01327 == 727) ) {
print "true"
}
}</lang>
C
Leading 0 means octal, 0x or 0X means hexadecimal. Otherwise, it is just decimal.
<lang c>#include <stdio.h>
int main() {
printf("%s\n",
( (727 == 0x2d7) &&
(727 == 01327) ) ? "true" : "false");
return 0;
}</lang>
C has no way of specifying integers in binary (if there's something like 0b..., it is not standard)
Common Lisp
(This is an interactive common lisp session)
binary: #b, octal: #o, hexadecimal: #x, any base from 2 to 36: #Nr
>(= 727 #b1011010111) T >(= 727 #o1327) T >(= 727 #x2d7) T >(= 727 #20r1g7) T
Forth
The standard method for entering numbers of a particular base is to set the user variable BASE to the desired radix from 2 to 36. There are also convenience words for setting the base to DECIMAL and HEX. <lang forth>
HEX FEEDFACE 2 BASE ! 1011001 DECIMAL 1234 : mask var @ [ base @ hex ] 3fff and [ base ! ] var ! ;
</lang> The Forth numeric parser will look for symbols embedded within the stream of digits to determine whether to interpret it as a single cell, double cell, or floating point literal ('e'). <lang forth>
1234 ( n ) 123.4 ( l h ) 123e4 ( F: n )
</lang>
Base prefixes
In addition, many Forths have extensions for using a prefix to temporarily override BASE when entering an integer literal. These are the prefixes supported by GNU Forth. <lang forth>
$feedface \ hexadecimal &1234 \ decimal %1001101 \ binary 'a \ base 256 (ASCII literal)
</lang> Some Forths also support "0xABCD" hex literals for compatibility with C-like languages.
Fortran
<lang fortran>program IntegerLiteral
implicit none integer, parameter :: dec = 727 integer, parameter :: hex = Z'2d7' integer, parameter :: oct = O'1327' integer, parameter :: bin = B'1011010111'
print *, dec, hex, oct, bin
end program IntegerLiteral</lang>
Outputs:
727 727 727 727
Modula-3
All numbers 2 to 16 are allowed to be bases. <lang modula3>MODULE Literals EXPORTS Main;
IMPORT IO;
BEGIN
IO.PutInt(16_2D7);
IO.Put(" ");
IO.PutInt(10_727);
IO.Put(" ");
IO.PutInt(8_1327);
IO.Put(" ");
IO.PutInt(2_1011010111);
IO.Put("\n");
END Literals.</lang>
The Fmt module also has optional arguments in it's numeric functions for setting the base.
Haskell
(This is an interactive ghci session)
Oct(leading 0o or 0O), Hex(leading 0x or 0X) <lang haskell> Prelude> 727 == 0o1327 True Prelude> 727 == 0x2d7 True </lang>
Java
Leading 0 means octal, 0x or 0X means hexadecimal. Otherwise, it is just decimal.
<lang java5>public class IntegerLiterals {
public static void main(String[] args) {
System.out.println( 727 == 0x2d7 &&
727 == 01327 );
}
}</lang>
Java has no way of specifying integers in binary.
You may also specify a long literal by adding an l or L (the latter form is preferred as the former looks like a "1") to the end (ex: long a = 574298540721727L), and this is required for numbers that are too large to be expressed as an int.
JavaScript
<lang javascript> if ( 727 == 0x2d7 &&
727 == 01327 )
window.alert("true");
</lang>
OCaml
(This is an interactive ocaml session)
Bin(leading 0b or 0B), Oct(leading 0o or 0O), Hex(leading 0x or 0X) <lang ocaml>
- 727 = 0b1011010111;;
- : bool = true
- 727 = 0o1327;;
- : bool = true
- 727 = 0x2d7;;
- : bool = true
- 12345 = 12_345 (* underscores are ignored; useful for keeping track of places *);;
- : bool = true </lang>
Literals for the other built-in integer types:
- 727l - int32
- 727L - int64
- 727n - nativeint
Perl
<lang perl> print "true\n" if ( 727 == 0x2d7 &&
727 == 01327 &&
727 == 0b1011010111 &&
12345 == 12_345 # underscores are ignored; useful for keeping track of places
);
</lang>
PHP
<lang php><?php if ( 727 == 0x2d7 &&
727 == 01327 ) echo "true\n";
?></lang>
Python
Python 3.0 brought in the binary literal and uses 0o or 0O exclusively for octal. <lang python>>>> # Bin(leading 0b or 0B), Oct(leading 0o or 0O), Dec, Hex(leading 0x or 0X), in order: >>> 0b1011010111 == 0o1327 == 727 == 0x2d7 True >>> </lang>
Python 2.6 has the binary and new octal formats of 3.0, as well as keeping the earlier leading 0 octal format of previous 2.X versions for compatability. <lang python>>>> # Bin(leading 0b or 0B), Oct(leading 0o or 0O, or just 0), Dec, Hex(leading 0x or 0X), in order: >>> 0b1011010111 == 0o1327 == 01327 == 727 == 0x2d7 True >>> </lang>
<lang python>>>> # Oct(leading 0), Dec, Hex(leading 0x or 0X), in order: >>> 01327 == 727 == 0x2d7 True >>> </lang>
In Python 2.x you may also specify a long literal by adding an l or L (the latter form is preferred as the former looks like a "1") to the end (ex: 574298540721727L), but this is optional, as integer literals that are too large for an int will be interpreted as a long.
Ruby
(This is an interactive irb session)
irb(main):001:0> 727 == 0b1011010111 => true irb(main):002:0> 727 == 0x2d7 => true irb(main):003:0> 727 == 01327 => true irb(main):001:0> 12345 == 12_345 # underscores are ignored; useful for keeping track of places => true
Scheme
(This is an interactive scheme session)
binary: #b, octal: #o, decimal: #d (optional obviously), hex: #x
> (= 727 #b1011010111) #t > (= 727 #o1327) #t > (= 727 #d727) #t > (= 727 #x2d7) #t
UNIX Shell
As manual states, 0x or 0X is the prefix for hexadecimal numbers, while 0 is the one for octal, and nothing means the number is decimal. But the sintax BASE#NUMBER can be used, with BASE going from 2 to 64, and the symbols used are digits, lowercase letters, uppercase letters, @ and _ in that order; if the BASE is less than or equal to 36, lowercase and uppercase letters can be used interchangeably to represent number from 10 and 35. (From the info manual of the Bash). This syntax works only in some circumstances, i.e. in the shell expansion (e.g. inside $(( ))) or using let.
dec=727 oct=$(( 01327 )) bin=$(( 2#1011010111 )) hex=$(( 0x2d7 )) # or e.g. let bin=2#1011010111 let "baseXX = 20#1g7"