#! /usr/bin/perl -w
use strict;

print largest(@ARGV)."\n";

sub largest {
  # Everything works mod $least
  my $least = min(@_);
  # We start off not knowing how to do anything.
  my @first = map {undef} 1..$least;
  # For technical reasons this needs to be 0 now,
  # and $least later.
  $first[0] = 0;
  for my $num (@_) {
    my @in_process = grep {defined($first[$_])} 0..($least - 1);
    while (@in_process) {
      my $to_process = shift @in_process;
      my $value = $first[$to_process] + $num;
      my $mod = $value % $least;
      if (not defined($first[$mod]) or $value < $first[$mod]) {
        $first[$mod] = $value;
    print "  $value = $mod (mod $least)\n";
    push @in_process, $mod;
      }
    }
  }
  $first[0] = $least;
  if (grep {not defined($_)} @first) {
    # We didn't reach one...
    return undef;
  }
  else {
    my $worst = max(@first);
    return $worst - $least;
  }
}

sub min {
  my $min = shift;
  for (@_) {
    $min = $_ if $_ < $min;
  }
  return $min;
}

sub max {
  my $max = shift;
  for (@_) {
    $max = $_ if $_ > $max;
  }
  return $max;
}
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