#!/usr/bin/perl -w use v5.16; use File::Slurper 'read_text'; sub compute { my @in = @_; my @out = (); my @d = split ",", read_text "day05"; for (my $ip = 0; $d[$ip] != 99; ) { my ($pm3, $pm2, $pm1, $op1, $op2) = split '', sprintf("%05d", $d[$ip]); my $op = $op1 . $op2; my $p1 = $pm1 ? $d[$ip+1] : $d[$d[$ip+1]]; my $p2 = $pm2 ? $d[$ip+2] : $d[$d[$ip+2]]; my $p3 = $pm3 ? $d[$ip+3] : $d[$d[$ip+3]]; if ($op == 1) { $d[$d[$ip+3]] = $p1 + $p2; $ip += 4; } elsif ($op == 2) { $d[$d[$ip+3]] = $p1 * $p2; $ip += 4; } elsif ($op == 3) { $d[$d[$ip+1]] = shift @in; $ip += 2; } elsif ($op == 4) { push @out, $p1; $ip += 2; } elsif ($op == 5) { $ip = $p1 ? $p2 : $ip + 3; } elsif ($op == 6) { $ip = !$p1 ? $p2 : $ip + 3; } elsif ($op == 7) { $d[$d[$ip+3]] = $p1 < $p2; $ip += 4; } elsif ($op == 8) { $d[$d[$ip+3]] = $p1 == $p2; $ip += 4; } } @out; } say((compute(1))[-1]); # 13978427 say compute(5); # 11189491