Next Greater Element I LeetCode solution in Java

1
class Solution {
2
  public int[] nextGreaterElement(int[] nums1, int[] nums2) {
3
    HashMap<Integer, Integer> map = new HashMap<>();
4
    Stack<Integer> stack = new Stack<>();
5
    int[] ans = new int[nums1.length];
6
    for (int i = 0; i < nums2.length; i++) {
7
      while (!stack.isEmpty() && nums2[i] > stack.peek()) {
8
        int temp = stack.pop();
9
        map.put(temp, nums2[i]);
10
      }
11
      stack.push(nums2[i]);
12
    }
13
    for (int i = 0; i < nums1.length; i++) {
14
      ans[i] = map.getOrDefault(nums1[i], -1);
15
    }
16
    return ans;
17
  }
18
}