($num,$base) = @ARGV;
$orig = $num;
$exp = int(log($num)/log($base));
while ($exp) {
  $try = $base ** $exp--;
  if ($try > $num) {
    $bin .= "0"; next 
  }
  $num -= $try if ($try <= $num);
  die "Nope!" if ($try <= $num);
  $bin .= "1"
}
if ($num > 1) {
  die "Nope!"
} else {
  $bin .= $num ? "1" : "0";
  print "$orig in base $base: $bin\n";
}