1145

/**
 * 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 {
public:
    bool ans=false;
    bool btreeGameWinningMove(TreeNode* root, int n, int x) {
        dfs(root, x, n);
        return ans;
    }

    int dfs(TreeNode *root, int x, int n){
        if(!root) return 0;
        int leftSize = dfs(root->left, x, n);
        int rightSize = dfs(root->right, x, n);
        int currCount = leftSize + rightSize + 1;
        if(root->val == x){
            ans = ((leftSize > n-leftSize) || (rightSize > n-rightSize) || (n-currCount > currCount));
        }
        return currCount;
    }

};