797D Broken BST

#include<iostream>#include<vector>#include<string>#include<set>#include<map>#include<algorithm>#include<queue>#include<stack>using namespace std;void get(int root, vector<int> &val, vector<int> &left, vector<int> &right, int min_val, int max_val, map<int, int> &dic1, map<int, int> &dic2, int &result){if (val[root] >= min_val&&val[root] <= max_val){dic1[val[root]] = 1;}else{result++;dic2[val[root]]++;}if (left[root] != -1) get(left[root], val, left, right, min_val, min(val[root], max_val), dic1, dic2, result);if (right[root] != -1) get(right[root], val, left, right, max(min_val, val[root]), max_val, dic1, dic2, result);}int main(){int n;while (cin >> n){vector<int> value(n + 1);vector<int> left(n + 1);vector<int> right(n + 1);vector<int> isroot(n + 1, true);map<int, int> dic1;map<int, int> dic2;for (int i = 1; i <= n; i++){cin >> value[i] >> left[i] >> right[i];if (left[i] != -1) isroot[left[i]] = false;if (right[i] != -1) isroot[right[i]] = false;}int root;for (int i = 1; i <= n; i++){if (isroot[i]){root = i;break;}}int up = INT_MAX;int down = INT_MIN;int result = 0;get(root, value, left, right, down, up, dic1, dic2, result);for (int i = 1; i <= n; i++){if (dic1[value[i]] && dic2[value[i]]){result -= dic2[value[i]];dic2[value[i]] = 0;}}cout << result << endl;}return 0;}