Submission #550550

#	Time	Username	Problem	Language	Result	Execution time	Memory
550550		krit3379	Power Plant (JOI20_power)	C++17	100 / 100	196 ms	29516 KiB

power

#include<bits/stdc++.h>
using namespace std;
#define N 200005

int dp[N],p[N],ans;
char s[N];
vector<int> g[N];

void dfs(int s,int f){
    int ma=0;
    for(auto x:g[s]){
        if(x==f)continue;
        dfs(x,s);
        dp[s]+=dp[x];
        ma=max(ma,dp[x]);
    }
    dp[s]-=p[s];
    dp[s]=max(dp[s],p[s]);
    ans=max({ans,ma+p[s],dp[s]});
}

int main(){
    int n,i,a,b;
    scanf("%d",&n);
    for(i=1;i<n;i++){
        scanf("%d %d",&a,&b);
        g[a].push_back(b);
        g[b].push_back(a);
    }
    scanf(" %s",s+1);
    for(i=1;i<=n;i++)p[i]=s[i]-'0';
    dfs(1,0);
    printf("%d",ans);
    return 0;
}

Compilation message (stderr)

power.cpp: In function 'int main()':
power.cpp:24:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   24 |     scanf("%d",&n);
      |     ~~~~~^~~~~~~~~
power.cpp:26:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   26 |         scanf("%d %d",&a,&b);
      |         ~~~~~^~~~~~~~~~~~~~~
power.cpp:30:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |     scanf(" %s",s+1);
      |     ~~~~~^~~~~~~~~~~

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