Advent of Code - adventofcode.com

# input reading elided

my %swap=( 'jmp' => 'nop', 'nop' => 'jmp' );

# Part 1:
my ( $p1_r, $p1_a ) = runcomp();
print "Part 1: $p1_r $p1_a\n";

for( my $ct=0; $ct < $psize ; $ct++ ) {
        my $old_instr = $ins[$ct];
        if( exists( $swap{$old_instr} ) ) {
                my $new_instr = $swap{$old_instr};
                $ins[$ct]=$new_instr;
                my ( $ret, $acc ) = runcomp();
                if( $ret eq "bounds" ) {
                        print "Part 2: Replacing $ct ($old_instr) with $new_instr return bounds error with acc=$acc\n";
                }
                $ins[$ct]=$old_instr;
        }
}

# runcomp function elided too