Submission #634654

#	Time	Username	Problem	Language	Result	Execution time	Memory
634654		PoPularPlusPlus	Power Plant (JOI20_power)	C++17	100 / 100	134 ms	25264 KiB

power

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ull unsigned long long 
#define pb(e) push_back(e)
#define sv(a) sort(a.begin(),a.end())
#define sa(a,n) sort(a,a+n)
#define mp(a,b) make_pair(a,b)
#define vf first
#define vs second
#define ar array
#define all(x) x.begin(),x.end()
const int inf = 0x3f3f3f3f;
const int mod = 1000000007; 
const double PI=3.14159265358979323846264338327950288419716939937510582097494459230;
bool remender(ll a , ll b){return a%b;}

//freopen("problemname.in", "r", stdin);
//freopen("problemname.out", "w", stdout);

const int N = 200003;

vector<int> adj[N];
string s;
int ans;

int dfs(int node , int par){
	if(s[node-1] == '0'){
		int sum = 0;
		for(int i : adj[node]){
			if(i!=par){
				sum += dfs(i,node);
			}
		}
		return sum;
	}
	int mx = 0;
	int sum = 0;
	for(int i : adj[node]){
		if(i != par){
		   int x = dfs(i , node);
		   mx = max(mx , x);
		   sum += x;
		}
	}
	ans = max(ans , mx + 1);
	return max(1 , sum - 1);
}

void solve(){
	int n;
	cin >> n;
	for(int i = 0; i < n-1; i++){
		int a , b;
		cin >> a >> b;
		adj[a].pb(b);
		adj[b].pb(a);
	}
	cin >> s;
	int cnt = 0;
	for(int i = 0; i < n; i++)cnt += (s[i]-'0');
	ans = 0;
	ans = max(ans , dfs(1,1));
	cout << ans << '\n';
}

int main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
	//int t;cin >> t;while(t--)
	solve();
	return 0;
}

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