제출 #1149929

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1149929		dosts	Power Plant (JOI20_power)	C++20	0 / 100	4 ms	9800 KiB

power

#include <bits/stdc++.h>
#pragma GCC target("avx2")
#pragma GCC optimize("O3,unroll-loops")
using namespace std;
#define int long long
#define pii pair<int,int>
#define ff first
#define ss second
#define sp << " " <<    
#define all(cont) cont.begin(),cont.end()
#define vi vector<int>

const int inf = 1e17,N = 3e5+1,MOD = 1e9+7,BL = 1000;

vi edges[N],dp(N);

string c;
int dfs(int node,int p) {
    int sm = 0;
    for (auto it : edges[node]) {
        if (it == p) continue;
        int d = dfs(it,node);
        dp[node] = max(dp[node],dp[it]);
        sm += d;
    }
    dp[node] = max(0ll,sm-(c[node-1] == '1'));
    if (c[node-1] == '1' && node != p) dp[node] = max(dp[node],1ll);
    return dp[node];
}
void solve() { 
    int n;
    cin >> n;
    for (int i=1;i<n;i++) {
        int a,b;
        cin >> a >> b;
        edges[a].push_back(b);
        edges[b].push_back(a);
    }
    cin >> c;
    if (n <= 2) {
        cout << count(all(c),'1') << '\n';
        return;
    }
    int ans = 0;
    for (int i=1;i<=n;i++) {
        dfs(i,i);
        ans = max(ans,dp[i]);
    }
    cout << ans << '\n';
}

int32_t main() { 
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    #ifdef Dodi 
        freopen("in.txt","r",stdin);
        freopen("out.txt","w",stdout);
    #endif
    int t = 1;
    //cin >> t;
    while (t --> 0) solve();
}

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