Submission #1114643

#	Time	Username	Problem	Language	Result	Execution time	Memory
1114643		Icelast	Power Plant (JOI20_power)	C++17	100 / 100	145 ms	26800 KiB

power

#include <iostream>
#include <bits/stdc++.h>
#define ll long long
using namespace std;
const ll maxn = 2*1e5+5, INF = 4e18+9;
void solve(){
    int n;
    cin >> n;
    vector<vector<int>> adj(n+1);
    for(int i = 1; i < n; i++){
        int u, v;
        cin >> u >> v;
        adj[u].push_back(v);
        adj[v].push_back(u);
    }
    string s;
    cin >> s;
    s = ' ' + s;
    vector<int> f(n+1, 0);
    int ans = 1;
    auto dfs = [&](auto dfs, int u, int p) -> void{
        int mx = 0;
        for(int v : adj[u]){
            if(v == p) continue;
            dfs(dfs, v, u);
            f[u] += f[v];
            mx = max(mx, f[v]);
        }
        ans = max(ans, mx + (s[u] == '1'));
        f[u] -= (s[u] == '1');
        f[u] = max(f[u], (int)(s[u] == '1'));
        ans = max(ans, f[u]);
    };
    dfs(dfs, 1, 0);
    cout << ans;
}
int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    solve();
}

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