in reply to using bits to print part of a string

I created the bit mask from the mask by replacing 0's by \x00 and 1's by \xff. Then, you can use bitwise & and can easily remove the resulting \x00's:
#!/usr/bin/perl use warnings; use strict; my $string = join q(), map int rand 10, 1 .. 400_000; my $mask = join q(), map int rand 2, 1 .. 400_000; $mask =~ tr/01/\x00\xff/; my $result = $string & $mask; $result =~ tr/\x00//d; print $result;
Updated: Using tr/ instead of s/ at line 10 speeds the method up.
لսႽ ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ