[leetcode][993] Cousins in Binary Tree : https://leetcode.com/problems/cousins-in-binary-tree/

Cousins in Binary Tree.cpp

/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 * };
 */
class Solution {
private:
    pair<int,int> parentAndDepth_x = {-1,-1};
    pair<int,int> parentAndDepth_y = {-1,-1};
    int X = 0;
    int Y = 0;
    
    void setParentAndDepth(TreeNode* root, int parent, int depth){
        if(root == NULL) return;
        int val = root->val;
        if(val == X)
            parentAndDepth_x = {parent, depth};
        if(val == Y)
            parentAndDepth_y = {parent, depth};
        setParentAndDepth(root->left, val, depth+1);
        setParentAndDepth(root->right, val, depth+1);
    }
    
public:
    bool isCousins(TreeNode* root, int x, int y) {
        X = x;
        Y = y;
        setParentAndDepth(root, -1, 0);
        return (parentAndDepth_x.first != parentAndDepth_y.first &&
                parentAndDepth_x.second == parentAndDepth_y.second);
    }
};