package q150

func twoSum(numbers []int, target int) []int {
	l, r := 0, len(numbers)-1

	for l < r {
		for numbers[r]+numbers[l] > target {
			r--
		}
		if numbers[r]+numbers[l] == target {
			return []int{l + 1, r + 1}
		}

		for numbers[r]+numbers[l] < target {
			l++
		}
		if numbers[r]+numbers[l] == target {
			return []int{l + 1, r + 1}
		}
	}
	return []int{} // impossible
}

var _ = twoSum