Decimal to Binary
Introduction
A smallish program to print in binary the first (integer) argument it receives on the command line.
Source
C
main(int c,int*v){for(c=32;c--;putchar(atoi(v[1])&1<<c?49:48));}
Perl
for($i=32;$i--;){print($ARGV[0]&1<<$i?'1':'0');}