use List::Util      qw( min );
use List::MoreUtils qw( any );

my $target = 5;
my @max = (7, 4);

my $time = 0;
my @status = (0) x @max;
my %seen;

for (;;) {
   die("Unable to solve the problem\n")
      if $seen{join('|', @status)}++;

   foreach (0..$#status) {
      next if $status[$_];
      $status[$_] = $max[$_];
      print("$time: begin $max[$_]\n");
   }

   last if any { $_ == $target } @status;

   my $elapsed_time = min(@status);
   $status[$_] = $status[$_] - $elapsed_time
      foreach 0..$#status;
   $time += $elapsed_time;
}

print("$time: begin cooking\n");
$time += $target;
print("$time: end cooking\n");