Submission #622014

#	Time	Username	Problem	Language	Result	Execution time	Memory
622014		MinaRagy06	Network (BOI15_net)	C++17	0 / 100	1 ms	340 KiB

net

#include <bits/stdc++.h>
using namespace std;
#define lesgooo ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0)
#define endl    '\n'
#define int     long long

signed main()
{
    lesgooo;
    int n, u, v;
    cin >> n;
    vector<int> adj[n];
    for (int i = 1; i < n; i++) cin >> u >> v, adj[--u].push_back(--v), adj[v].push_back(u);
    set<int> leaf;
    for (int i = 0;i < n; i++) if (adj[i].size() == 1) leaf.insert(i);
    cout << (leaf.size()+1)/2 << endl;
    int temp = *leaf.begin();
    while (leaf.size())
    {
        cout << *leaf.begin()+1 << " ", leaf.erase(leaf.begin());
        if (leaf.size()) cout << *leaf.begin()+1 << endl, leaf.erase(leaf.begin());
        else cout << temp+1 << endl;
    }
    return 0;
}

• Subtask 1: 0 / 18
• Subtask 2: 0 / 45
• Subtask 3: 0 / 37