rt，蒟蒻调了半天qwq

# include <iostream>
# include <vector>
using namespace std;
vector<int> son[1145];
int n,m,score[1145],dp[1145][1145];
void dfs(int idx){
	for (int s = 0;s < son[idx].size();s++){
		dfs(son[idx][s]);
		for (int npck = m;npck > 0;npck--){
			for (int pck = 0;pck < npck;pck++){
				dp[idx][npck] = \
				max(dp[idx][npck],\
				dp[idx][npck-pck] + dp[son[idx][s]][pck]);
			}
		}
	}
}int main(){
	cin >> n >> m;
	m++;
	for (int i = 1;i <= n;i++){
		int fa; cin >> fa >> score[i];
		dp[i][1] = score[i];
		son[fa].push_back(i);
		if (fa != 0) son[0].push_back(i);
	}dfs(0);
	cout << dp[0][m];
	return 0;
}