| # | Submission time | Handle | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 605843 | 2022-07-26T03:31:30 Z | buidangnguyen05 | Network (BOI15_net) | C++14 | 2000 ms | 91980 KB |
//source: https://oj.uz/problem/view/BOI15_net
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 1e6 + 10;
vector<int> adj[N];
vector<pair<int, int>> ans;
vector<int> dfs(int x, int par) {
if (adj[x].size() == 1) return vector<int>(1, x);
vector<int> cur;
for (int i : adj[x]) if (i != par) {
vector<int> v = dfs(i, x);
if (cur.size() < v.size()) swap(v, cur);
while (cur.size() + v.size() > 2 && v.size()) {
int p = cur.back(); cur.pop_back();
int q = v.back(); v.pop_back();
cerr << x << " " << p << " " << q << "\n";
ans.emplace_back(p, q);
}
for (int j : v) cur.push_back(j);
}
return cur;
}
signed main() {
cin.tie(0)->sync_with_stdio(0);
if (fopen("task.inp", "r")) {
freopen("task.inp", "r", stdin);
freopen("task.out", "w", stdout);
}
int n; cin >> n;
for (int i = 1; i < n; ++i) {
int x, y; cin >> x >> y;
adj[x].push_back(y); adj[y].push_back(x);
//ans.emplace_back(x, y);
}
int root = 0;
for (int i = 1; i <= n; ++i) if (adj[i].size() > 1 && !root) root = i;
//cerr << root << "\n";
vector<int> rem = dfs(root, 0);
if (rem.size() > 1) {
int u = rem.back(); rem.pop_back();
int v = rem.back(); rem.pop_back();
ans.emplace_back(u, v);
}
if (rem.size()) ans.emplace_back(rem.back(), root);
cout << ans.size() << "\n";
for (pair<int, int> i : ans) cout << i.first << " " << i.second << "\n";
}
Compilation message
| # | Verdict | Execution time | Memory | Grader output |
|---|---|---|---|---|
| 1 | Correct | 10 ms | 23804 KB | Output is correct |
| 2 | Correct | 10 ms | 23760 KB | Output is correct |
| 3 | Correct | 11 ms | 23764 KB | Output is correct |
| 4 | Correct | 10 ms | 23764 KB | Output is correct |
| 5 | Correct | 11 ms | 23764 KB | Output is correct |
| 6 | Correct | 11 ms | 23780 KB | Output is correct |
| 7 | Correct | 12 ms | 23712 KB | Output is correct |
| 8 | Correct | 12 ms | 23764 KB | Output is correct |
| 9 | Correct | 11 ms | 23764 KB | Output is correct |
| 10 | Correct | 13 ms | 23764 KB | Output is correct |
| 11 | Correct | 10 ms | 23692 KB | Output is correct |
| 12 | Correct | 12 ms | 23788 KB | Output is correct |
| 13 | Correct | 12 ms | 23764 KB | Output is correct |
| 14 | Correct | 14 ms | 23788 KB | Output is correct |
| 15 | Correct | 12 ms | 23680 KB | Output is correct |
| 16 | Correct | 11 ms | 23764 KB | Output is correct |
| 17 | Correct | 11 ms | 23764 KB | Output is correct |
| 18 | Correct | 11 ms | 23688 KB | Output is correct |
| 19 | Correct | 11 ms | 23764 KB | Output is correct |
| 20 | Correct | 11 ms | 23772 KB | Output is correct |
| # | Verdict | Execution time | Memory | Grader output |
|---|---|---|---|---|
| 1 | Correct | 10 ms | 23804 KB | Output is correct |
| 2 | Correct | 10 ms | 23760 KB | Output is correct |
| 3 | Correct | 11 ms | 23764 KB | Output is correct |
| 4 | Correct | 10 ms | 23764 KB | Output is correct |
| 5 | Correct | 11 ms | 23764 KB | Output is correct |
| 6 | Correct | 11 ms | 23780 KB | Output is correct |
| 7 | Correct | 12 ms | 23712 KB | Output is correct |
| 8 | Correct | 12 ms | 23764 KB | Output is correct |
| 9 | Correct | 11 ms | 23764 KB | Output is correct |
| 10 | Correct | 13 ms | 23764 KB | Output is correct |
| 11 | Correct | 10 ms | 23692 KB | Output is correct |
| 12 | Correct | 12 ms | 23788 KB | Output is correct |
| 13 | Correct | 12 ms | 23764 KB | Output is correct |
| 14 | Correct | 14 ms | 23788 KB | Output is correct |
| 15 | Correct | 12 ms | 23680 KB | Output is correct |
| 16 | Correct | 11 ms | 23764 KB | Output is correct |
| 17 | Correct | 11 ms | 23764 KB | Output is correct |
| 18 | Correct | 11 ms | 23688 KB | Output is correct |
| 19 | Correct | 11 ms | 23764 KB | Output is correct |
| 20 | Correct | 11 ms | 23772 KB | Output is correct |
| 21 | Correct | 11 ms | 23744 KB | Output is correct |
| 22 | Correct | 18 ms | 23892 KB | Output is correct |
| 23 | Correct | 18 ms | 23884 KB | Output is correct |
| 24 | Correct | 20 ms | 23892 KB | Output is correct |
| 25 | Correct | 18 ms | 23888 KB | Output is correct |
| 26 | Correct | 16 ms | 23844 KB | Output is correct |
| 27 | Correct | 21 ms | 23812 KB | Output is correct |
| 28 | Correct | 17 ms | 23892 KB | Output is correct |
| 29 | Correct | 19 ms | 23772 KB | Output is correct |
| 30 | Correct | 11 ms | 23740 KB | Output is correct |
| 31 | Correct | 17 ms | 23892 KB | Output is correct |
| 32 | Correct | 12 ms | 23716 KB | Output is correct |
| 33 | Correct | 11 ms | 23764 KB | Output is correct |
| 34 | Correct | 11 ms | 23764 KB | Output is correct |
| 35 | Correct | 11 ms | 23764 KB | Output is correct |
| 36 | Correct | 11 ms | 23764 KB | Output is correct |
| 37 | Correct | 13 ms | 23892 KB | Output is correct |
| 38 | Correct | 12 ms | 23904 KB | Output is correct |
| 39 | Correct | 11 ms | 23748 KB | Output is correct |
| 40 | Correct | 10 ms | 23764 KB | Output is correct |
| 41 | Correct | 13 ms | 23768 KB | Output is correct |
| 42 | Correct | 16 ms | 23840 KB | Output is correct |
| 43 | Correct | 15 ms | 23764 KB | Output is correct |
| 44 | Correct | 12 ms | 23764 KB | Output is correct |
| 45 | Correct | 14 ms | 23764 KB | Output is correct |
| 46 | Correct | 14 ms | 23764 KB | Output is correct |
| 47 | Correct | 11 ms | 23764 KB | Output is correct |
| 48 | Correct | 12 ms | 23724 KB | Output is correct |
| 49 | Correct | 16 ms | 23940 KB | Output is correct |
| 50 | Correct | 11 ms | 23764 KB | Output is correct |
| 51 | Correct | 11 ms | 23764 KB | Output is correct |
| 52 | Correct | 11 ms | 23764 KB | Output is correct |
| 53 | Correct | 12 ms | 23892 KB | Output is correct |
| 54 | Correct | 12 ms | 23708 KB | Output is correct |
| 55 | Correct | 14 ms | 23752 KB | Output is correct |
| 56 | Correct | 14 ms | 23848 KB | Output is correct |
| 57 | Correct | 13 ms | 23832 KB | Output is correct |
| 58 | Correct | 21 ms | 23920 KB | Output is correct |
| # | Verdict | Execution time | Memory | Grader output |
|---|---|---|---|---|
| 1 | Correct | 10 ms | 23804 KB | Output is correct |
| 2 | Correct | 10 ms | 23760 KB | Output is correct |
| 3 | Correct | 11 ms | 23764 KB | Output is correct |
| 4 | Correct | 10 ms | 23764 KB | Output is correct |
| 5 | Correct | 11 ms | 23764 KB | Output is correct |
| 6 | Correct | 11 ms | 23780 KB | Output is correct |
| 7 | Correct | 12 ms | 23712 KB | Output is correct |
| 8 | Correct | 12 ms | 23764 KB | Output is correct |
| 9 | Correct | 11 ms | 23764 KB | Output is correct |
| 10 | Correct | 13 ms | 23764 KB | Output is correct |
| 11 | Correct | 10 ms | 23692 KB | Output is correct |
| 12 | Correct | 12 ms | 23788 KB | Output is correct |
| 13 | Correct | 12 ms | 23764 KB | Output is correct |
| 14 | Correct | 14 ms | 23788 KB | Output is correct |
| 15 | Correct | 12 ms | 23680 KB | Output is correct |
| 16 | Correct | 11 ms | 23764 KB | Output is correct |
| 17 | Correct | 11 ms | 23764 KB | Output is correct |
| 18 | Correct | 11 ms | 23688 KB | Output is correct |
| 19 | Correct | 11 ms | 23764 KB | Output is correct |
| 20 | Correct | 11 ms | 23772 KB | Output is correct |
| 21 | Correct | 11 ms | 23744 KB | Output is correct |
| 22 | Correct | 18 ms | 23892 KB | Output is correct |
| 23 | Correct | 18 ms | 23884 KB | Output is correct |
| 24 | Correct | 20 ms | 23892 KB | Output is correct |
| 25 | Correct | 18 ms | 23888 KB | Output is correct |
| 26 | Correct | 16 ms | 23844 KB | Output is correct |
| 27 | Correct | 21 ms | 23812 KB | Output is correct |
| 28 | Correct | 17 ms | 23892 KB | Output is correct |
| 29 | Correct | 19 ms | 23772 KB | Output is correct |
| 30 | Correct | 11 ms | 23740 KB | Output is correct |
| 31 | Correct | 17 ms | 23892 KB | Output is correct |
| 32 | Correct | 12 ms | 23716 KB | Output is correct |
| 33 | Correct | 11 ms | 23764 KB | Output is correct |
| 34 | Correct | 11 ms | 23764 KB | Output is correct |
| 35 | Correct | 11 ms | 23764 KB | Output is correct |
| 36 | Correct | 11 ms | 23764 KB | Output is correct |
| 37 | Correct | 13 ms | 23892 KB | Output is correct |
| 38 | Correct | 12 ms | 23904 KB | Output is correct |
| 39 | Correct | 11 ms | 23748 KB | Output is correct |
| 40 | Correct | 10 ms | 23764 KB | Output is correct |
| 41 | Correct | 13 ms | 23768 KB | Output is correct |
| 42 | Correct | 16 ms | 23840 KB | Output is correct |
| 43 | Correct | 15 ms | 23764 KB | Output is correct |
| 44 | Correct | 12 ms | 23764 KB | Output is correct |
| 45 | Correct | 14 ms | 23764 KB | Output is correct |
| 46 | Correct | 14 ms | 23764 KB | Output is correct |
| 47 | Correct | 11 ms | 23764 KB | Output is correct |
| 48 | Correct | 12 ms | 23724 KB | Output is correct |
| 49 | Correct | 16 ms | 23940 KB | Output is correct |
| 50 | Correct | 11 ms | 23764 KB | Output is correct |
| 51 | Correct | 11 ms | 23764 KB | Output is correct |
| 52 | Correct | 11 ms | 23764 KB | Output is correct |
| 53 | Correct | 12 ms | 23892 KB | Output is correct |
| 54 | Correct | 12 ms | 23708 KB | Output is correct |
| 55 | Correct | 14 ms | 23752 KB | Output is correct |
| 56 | Correct | 14 ms | 23848 KB | Output is correct |
| 57 | Correct | 13 ms | 23832 KB | Output is correct |
| 58 | Correct | 21 ms | 23920 KB | Output is correct |
| 59 | Correct | 1355 ms | 44876 KB | Output is correct |
| 60 | Correct | 1607 ms | 47304 KB | Output is correct |
| 61 | Correct | 11 ms | 23764 KB | Output is correct |
| 62 | Correct | 13 ms | 23792 KB | Output is correct |
| 63 | Correct | 1315 ms | 43072 KB | Output is correct |
| 64 | Correct | 13 ms | 24788 KB | Output is correct |
| 65 | Correct | 23 ms | 28004 KB | Output is correct |
| 66 | Correct | 116 ms | 61352 KB | Output is correct |
| 67 | Correct | 455 ms | 89788 KB | Output is correct |
| 68 | Correct | 598 ms | 91980 KB | Output is correct |
| 69 | Correct | 73 ms | 24612 KB | Output is correct |
| 70 | Correct | 581 ms | 32248 KB | Output is correct |
| 71 | Execution timed out | 2095 ms | 51988 KB | Time limit exceeded |
| 72 | Halted | 0 ms | 0 KB | - |