Submission #550622

#	Time	Username	Problem	Language	Result	Execution time	Memory
550622		Pherokung	Power Plant (JOI20_power)	C++14	100 / 100	200 ms	28816 KiB

power

#include<bits/stdc++.h>
using namespace std;
#define N 200005
int n,u,v,dp[N],x[N],ans=0;
char s[N];
vector<int> adj[N];
int sol(int u,int p){
	int mx = 0;
	for(int v : adj[u]){
		if(v == p) continue;
		dp[u] += sol(v,u);
		mx = max(mx,dp[v]);
	}
	dp[u] = max(dp[u]-x[u],x[u]);
	ans = max({ans,dp[u],mx+x[u]});
	return dp[u];
}
int main(){
	scanf("%d",&n);
	for(int i=1;i<n;i++){
		scanf("%d%d",&u,&v);
		adj[u].push_back(v), adj[v].push_back(u);
	}
	scanf("%s",s+1);
	for(int i=1;i<=n;i++) if(s[i] == '1') x[i] = 1;
	sol(1,1);
	printf("%d",ans);
}

Compilation message (stderr)

power.cpp: In function 'int main()':
power.cpp:19:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   19 |  scanf("%d",&n);
      |  ~~~~~^~~~~~~~~
power.cpp:21:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   21 |   scanf("%d%d",&u,&v);
      |   ~~~~~^~~~~~~~~~~~~~
power.cpp:24:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   24 |  scanf("%s",s+1);
      |  ~~~~~^~~~~~~~~~

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