leetcode/1457-231126-pass/main.cpp

#include<bits/stdc++.h>
using namespace std;

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 pseudoPalindromicPaths (TreeNode* root) {
     const int length_limit = 1e5;
        int state[10]={};
        return find(root, state);
    }

    bool judge_is_permutation(int odd,int even){
        if(odd<=1)
            return true;
        else
            return false;
    }

    int find(TreeNode* Node, int* state){
        state[Node->val] += 1;
        if(Node->left == NULL && Node->right == NULL){
            int odd = 0;
            int even = 0;
            for(int i = 1 ; i <= 9 ;i++){
                if(state[i] > 0){
                    if(state[i]%2)
                        odd++;
                    else
                        even++;
                }
            }
            // for(int i = 1 ;i <=9;i++){
            //     cout<<state[i]<<' ';
            // }
            cout<<endl;
            if(judge_is_permutation(odd,even)){
                state[Node->val]-=1;
                return 1;
            }
            else{
                state[Node->val]-=1;
                return 0;
            }
        }
        int rlt = 0;
        if(Node->left!= NULL){
            rlt += find(Node->left,state);
        }
        if(Node->right!= NULL){
            rlt += find(Node->right,state);
        }
        state[Node->val]-=1;
        return rlt;
    }
};

int main(){
    return 0;
}