Submission #534694

#	Time	Username	Problem	Language	Result	Execution time	Memory
534694		michao	Power Plant (JOI20_power)	C++14	47 / 100	1502 ms	45380 KiB

power

#include <bits/stdc++.h>
#define int long long
#define mp make_pair
#define pb push_back
#define ld long double
#define pii pair<int,int>
#define sz(x) (int)x.size()
#define piii pair<pii,pii>
#define precise cout<<fixed<<setprecision(10)
#define st first
#define nd second
#define ins insert
#define vi vector<int>
#define BOOST ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0)
using namespace std;
const int MAX=2e5+5;
vi P[MAX];
int c[MAX];
int dp[MAX];
char s[MAX];
int ans=0;

void dfs(int u,int fa){
	vi d;
	d.clear();
	vi wrzut;
	for (auto it:P[u]){
		if (it==fa)continue;
		dfs(it,u);
		d.pb(it);
		wrzut.pb(dp[it]);
	}
	
	if (c[u]==0){
		for (auto v:d)dp[u]+=dp[v];
		ans=max(ans,dp[u]);
	}
	else{
		assert(c[u]==1);
		int sum=0;
		for (auto v:d)sum+=dp[v];
		if (sum==0)dp[u]=1,ans=max(ans,dp[u]);
		else{
			dp[u]=max(1LL,sum-1);
			sort(wrzut.begin(),wrzut.end());
			if (sz(wrzut)){
				ans=max(ans,wrzut.back()+1);
			}
			ans=max(ans,dp[u]);
		}
	}
}
int32_t main(){
  BOOST;
  int n;
  cin>>n;
  for (int i=1;i<=n-1;i++){
		int a,b;
		cin>>a>>b;
		P[a].pb(b);
		P[b].pb(a);
  }
  for (int i=1;i<=n;i++){
		cin>>s[i];
		c[i]=s[i]-'0';
  }
  dfs(1,-1);
  for (int i=1;i<=n;i++)cerr<<"DPEK "<<i<<" "<<dp[i]<<"\n";
  cout<<ans;
  return 0; 
}

• Subtask 1: 6 / 6
• Subtask 2: 41 / 41
• Subtask 3: 0 / 53