package main

func nextGreaterElement(nums1 []int, nums2 []int) (res []int) {
	n, m, stack, idxMap := len(nums1), len(nums2), []int{nums2[len(nums2)-1]}, make(map[int]int)
	idxMap[nums2[len(nums2)-1]] = -1
	for i := m - 2 ; i >= 0 ; i -- {
		for len(stack) > 0 && nums2[i] > stack[len(stack)-1] {
			stack = stack[:len(stack) - 1]
		}
		idxMap[nums2[i]] = -1
		if len(stack) > 0 {
			idxMap[nums2[i]] = stack[len(stack)-1]
		}
		stack = append(stack, nums2[i])
	}
	for i := 0 ; i < n ; i ++ {
		if v , ok := idxMap[nums1[i]] ; ok {
			res = append(res, v)
		}
	}
	return res
}

func main() {

}