/**
 * 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:
    int num = 0, res = 0;
    bool check() {
        int sum = 0;
        for (int i = 1; i <= 9; i++) {
            if (num & (1 << i)) sum ++;
        }
        return sum <= 1;
    }
    void change(int& bit) {
        int temp = (1 << bit);
        num = num ^ temp;
    }
    void solution(TreeNode* root) {
        change(root->val);
        if (!root->left && !root->right) {
            if (check()) res++;
            change(root->val);
            return;
        }
        if (root->left) pseudoPalindromicPaths(root->left);
        if (root->right) pseudoPalindromicPaths(root->right);
        change(root->val);
    }
    int pseudoPalindromicPaths (TreeNode* root) {
        solution(root);
        return res;
    }
};