Laskettelukeskus

#include <iostream>
#include <bits/stdc++.h>

using namespace std;
typedef unsigned long long ll;
const int N = 100007;
int n;
ll c[N];
int parent[N];
vector<int> child[N];
vector<int> lst;
int states[N] = {0};
ll cnt[N];

bool dfs(int s) {
    if (states[s] == 1) return false;
    if (states[s] == 0)
        states[s] = 1;
    if (states[s] == 1) {
        for (auto u: child[s]) {
            if (dfs(u) == false)
                return false;
        }
        lst.push_back(s);
    }
    states[s] = 2;
    return true;
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cin >> n;
    int a, b;
    for (int i=1; i<n; i++) {
        cin >> a >> b;
        child[a].push_back(b);
        parent[b] = a;
    }
    for (int i=1; i<=n; i++) {
        cin >> c[i];
    }
    parent[1] = 0;
    dfs(1);
    for (auto curr: lst) {
        if (c[curr] > cnt[curr])
            cnt[curr] = c[curr];
        cnt[parent[curr]] += cnt[curr];
    }
    cout << cnt[1] << "\n";
    return 0;
}

Test 1

Group: 1, 2

Verdict: ACCEPTED

Test 2

Group: 1, 2

Verdict: ACCEPTED

Test 3

Group: 1, 2

Verdict: ACCEPTED

Test 4

Group: 2

Verdict: ACCEPTED

Test 5

Group: 2

Verdict: ACCEPTED

Test 6

Group: 1, 2

Verdict: ACCEPTED

Test 7

Group: 2

Verdict: ACCEPTED

Test 8

Group: 1, 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: ACCEPTED

Test 10

Group: 1, 2

Verdict: ACCEPTED

Test 11

Group: 2

Verdict: ACCEPTED

Test 12

Group: 1, 2

Verdict: ACCEPTED

Test 13

Group: 2

Verdict: ACCEPTED