| # |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
| 655925 |
2022-11-06T05:51:00 Z |
Behradm |
Network (BOI15_net) |
C++17 |
|
412 ms |
40812 KB |
/*\ In The Name Of GOD
* Beyrad :D
\*/
#include "bits/stdc++.h"
#define sz(x) ((int) (x).size())
using namespace std;
const int N = 5e5 + 11;
int st[N];
int T = 0;
vector<int> g[N];
void dfs(int u, int p) {
st[u] = T++;
for (int v : g[u]) {
if (v != p)
dfs(v, u);
}
}
signed main() {
ios::sync_with_stdio(false);
cin.tie(0), cout.tie(0);
int n;
cin >> n;
for (int i = 0; i < n - 1; i++) {
int u, v;
cin >> u >> v;
--u, --v;
g[u].push_back(v);
g[v].push_back(u);
}
int rt = 0;
for (int i = 0; i < n; i++)
if (sz(g[i]) >= 2)
rt = i;
dfs(rt, -1);
vector<pair<int, int>> a;
for (int i = 0; i < n; i++)
if (sz(g[i]) == 1)
a.emplace_back(st[i], i);
sort(a.begin(), a.end());
int k = sz(a);
cout << (k + 1) / 2 << '\n';
for (int i = 0; i < k / 2; i++)
cout << a[i].second + 1 << " " << a[i + (k + 1) / 2].second + 1 << '\n';
if (k % 2 == 1)
cout << a[k / 2].second + 1 << " " << rt + 1 << '\n';
return 0;
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 2 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 3 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 4 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 5 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 6 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 7 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 8 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 9 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 10 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 11 |
Correct |
6 ms |
11964 KB |
Output is correct |
| 12 |
Correct |
6 ms |
12020 KB |
Output is correct |
| 13 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 14 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 15 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 16 |
Correct |
8 ms |
12008 KB |
Output is correct |
| 17 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 18 |
Correct |
6 ms |
12068 KB |
Output is correct |
| 19 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 20 |
Correct |
6 ms |
11988 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 2 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 3 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 4 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 5 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 6 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 7 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 8 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 9 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 10 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 11 |
Correct |
6 ms |
11964 KB |
Output is correct |
| 12 |
Correct |
6 ms |
12020 KB |
Output is correct |
| 13 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 14 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 15 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 16 |
Correct |
8 ms |
12008 KB |
Output is correct |
| 17 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 18 |
Correct |
6 ms |
12068 KB |
Output is correct |
| 19 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 20 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 21 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 22 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 23 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 24 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 25 |
Correct |
6 ms |
12116 KB |
Output is correct |
| 26 |
Correct |
6 ms |
12116 KB |
Output is correct |
| 27 |
Correct |
7 ms |
12184 KB |
Output is correct |
| 28 |
Correct |
8 ms |
12116 KB |
Output is correct |
| 29 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 30 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 31 |
Correct |
7 ms |
12180 KB |
Output is correct |
| 32 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 33 |
Correct |
12 ms |
11944 KB |
Output is correct |
| 34 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 35 |
Correct |
8 ms |
12064 KB |
Output is correct |
| 36 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 37 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 38 |
Correct |
8 ms |
12116 KB |
Output is correct |
| 39 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 40 |
Correct |
7 ms |
11972 KB |
Output is correct |
| 41 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 42 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 43 |
Correct |
10 ms |
12116 KB |
Output is correct |
| 44 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 45 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 46 |
Correct |
9 ms |
12116 KB |
Output is correct |
| 47 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 48 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 49 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 50 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 51 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 52 |
Correct |
14 ms |
12052 KB |
Output is correct |
| 53 |
Correct |
7 ms |
12072 KB |
Output is correct |
| 54 |
Correct |
7 ms |
11944 KB |
Output is correct |
| 55 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 56 |
Correct |
7 ms |
12068 KB |
Output is correct |
| 57 |
Correct |
7 ms |
12012 KB |
Output is correct |
| 58 |
Correct |
7 ms |
12200 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 2 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 3 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 4 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 5 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 6 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 7 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 8 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 9 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 10 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 11 |
Correct |
6 ms |
11964 KB |
Output is correct |
| 12 |
Correct |
6 ms |
12020 KB |
Output is correct |
| 13 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 14 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 15 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 16 |
Correct |
8 ms |
12008 KB |
Output is correct |
| 17 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 18 |
Correct |
6 ms |
12068 KB |
Output is correct |
| 19 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 20 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 21 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 22 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 23 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 24 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 25 |
Correct |
6 ms |
12116 KB |
Output is correct |
| 26 |
Correct |
6 ms |
12116 KB |
Output is correct |
| 27 |
Correct |
7 ms |
12184 KB |
Output is correct |
| 28 |
Correct |
8 ms |
12116 KB |
Output is correct |
| 29 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 30 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 31 |
Correct |
7 ms |
12180 KB |
Output is correct |
| 32 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 33 |
Correct |
12 ms |
11944 KB |
Output is correct |
| 34 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 35 |
Correct |
8 ms |
12064 KB |
Output is correct |
| 36 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 37 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 38 |
Correct |
8 ms |
12116 KB |
Output is correct |
| 39 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 40 |
Correct |
7 ms |
11972 KB |
Output is correct |
| 41 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 42 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 43 |
Correct |
10 ms |
12116 KB |
Output is correct |
| 44 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 45 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 46 |
Correct |
9 ms |
12116 KB |
Output is correct |
| 47 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 48 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 49 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 50 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 51 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 52 |
Correct |
14 ms |
12052 KB |
Output is correct |
| 53 |
Correct |
7 ms |
12072 KB |
Output is correct |
| 54 |
Correct |
7 ms |
11944 KB |
Output is correct |
| 55 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 56 |
Correct |
7 ms |
12068 KB |
Output is correct |
| 57 |
Correct |
7 ms |
12012 KB |
Output is correct |
| 58 |
Correct |
7 ms |
12200 KB |
Output is correct |
| 59 |
Correct |
314 ms |
32908 KB |
Output is correct |
| 60 |
Correct |
386 ms |
35396 KB |
Output is correct |
| 61 |
Correct |
7 ms |
12040 KB |
Output is correct |
| 62 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 63 |
Correct |
294 ms |
30976 KB |
Output is correct |
| 64 |
Correct |
8 ms |
12244 KB |
Output is correct |
| 65 |
Correct |
17 ms |
13268 KB |
Output is correct |
| 66 |
Correct |
104 ms |
20836 KB |
Output is correct |
| 67 |
Correct |
398 ms |
40812 KB |
Output is correct |
| 68 |
Correct |
412 ms |
37940 KB |
Output is correct |
| 69 |
Correct |
13 ms |
12884 KB |
Output is correct |
| 70 |
Correct |
77 ms |
20440 KB |
Output is correct |
| 71 |
Correct |
296 ms |
39000 KB |
Output is correct |
| 72 |
Correct |
312 ms |
38156 KB |
Output is correct |
| 73 |
Correct |
80 ms |
18240 KB |
Output is correct |
| 74 |
Correct |
384 ms |
33908 KB |
Output is correct |
| 75 |
Correct |
35 ms |
15056 KB |
Output is correct |
| 76 |
Correct |
288 ms |
38648 KB |
Output is correct |
| 77 |
Correct |
297 ms |
39012 KB |
Output is correct |
| 78 |
Correct |
26 ms |
14676 KB |
Output is correct |
| 79 |
Correct |
393 ms |
34716 KB |
Output is correct |
| 80 |
Correct |
8 ms |
12244 KB |
Output is correct |
| 81 |
Correct |
106 ms |
20344 KB |
Output is correct |
| 82 |
Correct |
328 ms |
36468 KB |
Output is correct |
| 83 |
Correct |
380 ms |
33896 KB |
Output is correct |
| 84 |
Correct |
376 ms |
34012 KB |
Output is correct |
| 85 |
Correct |
389 ms |
34008 KB |
Output is correct |
| 86 |
Correct |
379 ms |
35400 KB |
Output is correct |
| 87 |
Correct |
380 ms |
35388 KB |
Output is correct |
