Submission #755488

#	Time	Username	Problem	Language	Result	Execution time	Memory
755488		drdilyor	Pipes (BOI13_pipes)	C++17	65 / 100	65 ms	9176 KiB

pipes

#include <bits/stdc++.h>

using namespace std;
using ll = long long;
const int inf = 1e9;
const ll infl = 1e18;

signed main() {
    cin.tie(0)->sync_with_stdio(0);
    int n, m;
    cin >> n >> m;
    if (n != m+1) {
        if (n == m) exit(1);
        cout << 0 << '\n';
        return 0;
    }

    vector<int> arr(n);
    for (int& i : arr) cin >> i;

    vector<vector<pair<int,int>>> adj(n);
    for (int i = 0; i < m; i++) {
        int u, v;
        cin >> u >> v;
        u--;v--;
        adj[u].push_back({v, i});
        adj[v].push_back({u, i});
    }

    vector<int> ans(m);
    auto dfs = [&](auto& dfs, int i, int p =-1,int pei=-1) ->void {
        int c = 0;
        for (auto [e, ei]: adj[i]) {
            if (e == p) continue;
            c++;
            dfs(dfs, e, i, ei);
        }
        if (p!=-1) {
            ans[pei] = arr[i];
            arr[p] -= arr[i];
        }
    };
    dfs(dfs, 0);
    for (int i : ans) cout << i*2<< ' ';
    cout << '\n';
}

• Subtask 1: 30 / 30
• Subtask 2: 35 / 70