leetcode

0 class Solution {

1 public:

2 int maxAncestorDiff(TreeNode *root) {

3 if (!root) return 0;

4 int res = 0;

5 stack<tuple<TreeNode *, int, int>> st;

6 st.push({root, root->val, root->val});

7 while (!st.empty()) {

8 auto [root, maxi, mini] = st.top();

9 st.pop();

10 res = max({res, abs(maxi - root->val), abs(mini - root->val)});

11 maxi = max(maxi, root->val), mini = min(mini, root->val);

12 if (root->left) st.push({root->left, maxi, mini});

13 if (root->right) st.push({root->right, maxi, mini});

14 }

15 return res;

16 }

17 };