Submission #4032066

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Source Code Expand

#include "bits/stdc++.h"

using namespace std;

int cs[1<<10], ans = 0;
vector<int> adj[1<<10];

int dfs(int v)
{
	if (cs[v]) return cs[v];
	vector<int> res;
	for (int nv : adj[v])
	{
		res.push_back(dfs(nv));
	}
	sort(res.begin(), res.end());
	int m = res[0];
	for (int r : res)
	{
		ans += r - m;
	}
	return m;
}

void solve()
{
	int N, M;
	cin >> N >> M;
	for (int i = 1; i < N; i++)
	{
		int p;
		cin >> p;
		adj[p].push_back(i);
	}
	for (int i = 0; i < M; i++)
	{
		int b, c;
		cin >> b >> c;
		cs[b] = c;
	}
	for (int v : adj[0])
	{
		ans += dfs(v);
	}

	cout << ans << endl;
}

int main(void)
{
	solve();
	//cout << "yui(*-v・)yui" << endl;
	return 0;
}

Submission Info

Judge Result