Submission #599287

#	Time	Username	Problem	Language	Result	Execution time	Memory
599287		Jomnoi	Power Plant (JOI20_power)	C++17	100 / 100	218 ms	29260 KiB

power

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

const int MAX_N = 2e5 + 5;

int ans;
vector <int> graph[MAX_N];
int power[MAX_N];
int dp[MAX_N];

void dfs(int u, int p) {
    int ma = 0;
    for(auto v : graph[u]) {
        if(v == p) {
            continue;
        }

        dfs(v, u);

        ma = max(ma, dp[v]);
        dp[u] += dp[v];
    }

    dp[u] = max(dp[u] - power[u], power[u]);

    ans = max({ans, dp[u], ma + power[u]});
}

int main() {
    cin.tie(nullptr)->sync_with_stdio(false);

    int N;
    cin >> N;

    for(int i = 1; i <= N - 1; i++) {
        int a, b;
        cin >> a >> b;

        graph[a].push_back(b);
        graph[b].push_back(a);
    }

    for(int i = 1; i <= N; i++) {
        char c;
        cin >> c;

        power[i] = c - '0';
    }

    dfs(1, -1);

    cout << ans;
    return 0;
}

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