#!/usr/bin/env perl

use strict;
use warnings;

my $var1 = 0b00010100;
my $var2 = 0b00000110;

my $fmt = "%08b\n";

print "Initial:\n";
printf $fmt, $var1;
printf $fmt, $var2;

for my $bit (0, 1, 4) {
    print "Bit $bit off:\n";
    $var1 = set_bit_off($bit, $var1);
    printf $fmt, $var1;
    $var2 = set_bit_off($bit, $var2);
    printf $fmt, $var2;
}

sub set_bit_off {
    my ($bit, $num) = @_;

    my $mask = 1 << $bit;

    $num ^= $mask if $num & $mask;

    return $num;
}