func nesting(s string) int {
	if s == "" {
		return 1
	}

	depth := 0
	for i := 0; i < len(s); i++ {
		if s[i] == ')' {
			if depth == 0 {
				return 0
			}
			depth--
		} else {
			depth++
		}
	}

	if depth == 0 {
		return 1
	}

	return 0
}