有没有大佬能告诉我D题哪里错了

写的头昏脑花的，自己写了几个案例都过了，但不知道错哪了，求教。

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

struct NODE {
	int cnt_son;
	int son[2005];
	int father;
	long long int energy;
} parent[200005];

int main() {
	int n,  sum1 = 0, maxi = 1, f = 0, a, b[100005] = {0};
    long long int res=0;
	cin >> n;
	for (int i = 0; i < n - 1; i++) {
		cin >> a;
		parent[i + 2].father = a;
		parent[a].cnt_son++;
		parent[a].son[parent[a].cnt_son] = i + 2;
	}
	for (int i = 0; i < n; i++) {
		cin >> b[i];
		sum1 += b[i];
	}
	sort(b, b + n);
	for (int i = 1; i <= n; i++) {
		if (parent[maxi].cnt_son < parent[i].cnt_son)
			maxi = i;
	}
	for (int k = parent[maxi].cnt_son; k >= 0 ; k--) {
		for (int i = 1; i <= n; i++) {
			if (parent[i].cnt_son == k) {
				parent[i].energy = b[f];
				f++;
			}
		}
	}
	for (int k = 0; k <= parent[maxi].cnt_son ; k++) {
		for (int i = 1; i <= n; i++) {
			if (parent[i].cnt_son == k) {
				parent[parent[i].father].energy += parent[i].energy;

			}
		}
	}
	for (int i = 1; i <= n; i++) {
		res+=parent[i].energy;	
	}
	cout<<res;
}