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// @Title: 下一个更大元素 I (Next Greater Element I)
// @Author: 15816537946@163.com
// @Date: 2021-10-26 15:38:28
// @Runtime: 0 ms
// @Memory: 3.4 MB
func nextGreaterElement(nums1 []int, nums2 []int) []int {
	// 单调栈+哈希表
	mp := map[int]int{}
	stack := []int{}

	for i := len(nums2) - 1; i >= 0; i-- {
		num := nums2[i]
		for len(stack) > 0 && num > stack[len(stack)-1] {
			stack = stack[:len(stack)-1]
		}

		if len(stack) > 0 {
			mp[num] = stack[len(stack)-1]
		} else {
			mp[num] = -1
		}

		stack = append(stack, num)

	}

	res := make([]int, len(nums1))
	for i, v := range nums1 {
		res[i] = mp[v]
	}

	return res

}