Lowest Common Ancestor of Deepest Leaves（C++最深叶节点的最近公共祖先）

缺乏、安全感 2022-11-19 12:43 137阅读 0赞

解题思路：

（1）标记每个节点是否包含最深叶子结点

参考网址：[https://leetcode.com/problems/lowest-common-ancestor-of-deepest-leaves/discuss/334577/JavaC%2B%2BPython-Two-Recursive-Solution][https_leetcode.com_problems_lowest-common-ancestor-of-deepest-leaves_discuss_334577_JavaC_2B_2BPython-Two-Recursive-Solution]

/**
     * Definition for a binary tree node.
     * struct TreeNode {
     *     int val;
     *     TreeNode *left;
     *     TreeNode *right;
     *     TreeNode() : val(0), left(nullptr), right(nullptr) {}
     *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
     *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
     * };
     */
    class Solution {
    private:
        TreeNode *temp=NULL;
        int deepest = 0;
    public:
        int postorder(TreeNode *root,int depth) {
            deepest = max(deepest,depth);
            if(!root) return depth;
            auto left=postorder(root->left,depth+1);
            auto right=postorder(root->right,depth+1);
            
            if(left==deepest && right==deepest) {
                temp=root;
            }
            return max(left,right);
        }
        
        TreeNode* lcaDeepestLeaves(TreeNode* root) {
            postorder(root,0);
            return temp;
        }
    };

[https_leetcode.com_problems_lowest-common-ancestor-of-deepest-leaves_discuss_334577_JavaC_2B_2BPython-Two-Recursive-Solution]: https://leetcode.com/problems/lowest-common-ancestor-of-deepest-leaves/discuss/334577/JavaC%2B%2BPython-Two-Recursive-Solution