Submission #1054976

#	Time	Username	Problem	Language	Result	Execution time	Memory
1054976		Sharky	Power Plant (JOI20_power)	C++17	100 / 100	66 ms	30036 KiB

power

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

const int N = 200005;
int n, dp[N], s[N], pa[N], ans = 1;
vector<int> adj[N];

void dfs(int u, int p) {
    for (int v : adj[u]) {
        if (v == p) continue;
        pa[v] = u;
        dfs(v, u);
        dp[u] += max(s[v], dp[v]);
        ans = max(ans, max(s[v], dp[v]) + s[u]);
    }
    dp[u] -= s[u];
    if (u != 1) ans = max(ans, dp[u] + s[pa[u]]);
    else ans = max(ans, dp[u]);
}

int main() {
    ios::sync_with_stdio(0); cin.tie(0);
    cin >> n;
    for (int i = 1; i < n; i++) {
        int a, b;
        cin >> a >> b;
        adj[a].push_back(b);
        adj[b].push_back(a);
    }
    for (int i = 1; i <= n; i++) {
        char c;
        cin >> c;
        s[i] = c - '0';
    }
    dfs(1, -1);
    cout << ans << '\n';
}

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