Submission #763283

#	Time	Username	Problem	Language	Result	Execution time	Memory
763283		vjudge1	Power Plant (JOI20_power)	C++17	100 / 100	120 ms	26572 KiB

power

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

const int NM = 2e5;

int N, plant[NM+5], dp[NM+5], ans = 0;
vector <int> adj[NM+5];

void DFS(int u, int par){
	int tmp = 0;
	for (int i = 0; i < adj[u].size(); i++){
		int v = adj[u][i];
		if (v == par) continue;
		DFS(v, u);
		dp[u] += dp[v];
		tmp = max(tmp, dp[v]);
	}
	dp[u] -= plant[u];
	dp[u] = max(dp[u], plant[u]);
	ans = max(ans, dp[u]);
	ans = max(ans, tmp+plant[u]);
}

int main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin >> N;
	for (int i = 1; i < N; i++){
		int u, v;
		cin >> u >> v;
		adj[u].push_back(v);
		adj[v].push_back(u);
	}
	for (int i = 1; i <= N; i++){
		char ch; cin >> ch;
		plant[i] = ch-'0';
	}
	DFS(1, 1);
	cout << ans;
	return 0;
}

Compilation message (stderr)

power.cpp: In function 'void DFS(int, int)':
power.cpp:11:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   11 |  for (int i = 0; i < adj[u].size(); i++){
      |                  ~~^~~~~~~~~~~~~~~

• Subtask 1: 6 / 6
• Subtask 2: 41 / 41
• Subtask 3: 53 / 53