Submission #514856

#	Time	Username	Problem	Language	Result	Execution time	Memory
514856		ACE_	Power Plant (JOI20_power)	C++14	100 / 100	284 ms	28860 KiB

power

#include<bits/stdc++.h>
using namespace std;
const int maxn = 2e5 + 5;
int t, dp[maxn], n, ans;
vector<int> V[maxn];
string s;
void dfs(int u,int p) {
	int m = 0, all = 0;
	for(int i = 0; i < V[u].size(); i++) {
		if(V[u][i] == p) continue;
		dfs(V[u][i], u);
		all += dp[V[u][i]];
		m = max(m, dp[V[u][i]]);
	}
	dp[u] = max(m - (s[u] == '1'), 0 + (s[u] == '1'));
	dp[u] = max(dp[u], all  - (s[u] == '1'));
	ans = max(ans, m + (s[u] == '1')); ans = max(ans, dp[u]);
}
main(){
	cin >> n;
	for(int i = 2; i <= n; i++) {
		int u,v;
		cin >> u >> v;
		V[u].push_back(v); V[v].push_back(u);
	}
	cin >> s; s = '#' + s;
	dfs(1, 0);
	cout << max(ans, dp[1]);
}

Compilation message (stderr)

power.cpp: In function 'void dfs(int, int)':
power.cpp:9:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    9 |  for(int i = 0; i < V[u].size(); i++) {
      |                 ~~^~~~~~~~~~~~~
power.cpp: At global scope:
power.cpp:19:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   19 | main(){
      | ^~~~

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