use lib $*PROGRAM.parent.parent;
use Lib;

sub safe($report) {
  my $diff = $report.rotor(2=>-1).map({ $_[1] - $_[0] }).List;
  so (1 <= $diff.all <= 3 or -3 <= $diff.all <= -1)
}

grammar Solution does AOC {
  token TOP { (^^ <report> \n)+ { make $/[0]>><report>>>.made; } }
  token report { (<num> \h*)+ { make $/[0]>><num>>>.made;} }
  token num { \d+ { make val($/.Str) } }

  method part1(::?CLASS:U: $v) {
    $v.map(&safe).Bag{True};
  }

  method part2(::?CLASS:U: $v) {
    $v.map({so safe(.combinations(.elems - 1).any)}).Bag{True}
  }
}


Solution.main()