| # |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
| 113175 |
2019-05-24T07:26:12 Z |
rkocharyan |
Network (BOI15_net) |
C++14 |
|
632 ms |
49956 KB |
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 5e5 + 7;
vector <int> g[N];
vector <int> l;
int tin[N];
int timer;
void dfs(int v, int pr) {
tin[v] = timer++;
if (g[v].size() == 1) {
l.push_back(v);
}
for (int to : g[v]) {
if (to != pr) {
dfs(to, v);
}
}
}
int main() {
ios::sync_with_stdio(0);
cin.tie(0);
int n;
cin >> n;
for (int i = 0; i < n - 1; i++) {
int a, b;
cin >> a >> b;
a--, b--;
g[a].push_back(b);
g[b].push_back(a);
}
dfs(0, -1);
sort(l.begin(), l.end(), [&] (int a, int b) {
return tin[a] < tin[b];
});
int k = (int) l.size();
int m = k / 2;
cout << (k + 1) / 2 << '\n';
for (int i = 0; i < (k + 1) / 2; i++) {
cout << l[i] + 1 << ' ' << l[(i + m) % k] + 1 << '\n';
}
return 0;
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 2 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 3 |
Correct |
14 ms |
12160 KB |
Output is correct |
| 4 |
Correct |
13 ms |
12032 KB |
Output is correct |
| 5 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 6 |
Correct |
13 ms |
12160 KB |
Output is correct |
| 7 |
Correct |
13 ms |
12160 KB |
Output is correct |
| 8 |
Correct |
11 ms |
12028 KB |
Output is correct |
| 9 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 10 |
Correct |
11 ms |
12032 KB |
Output is correct |
| 11 |
Correct |
11 ms |
12032 KB |
Output is correct |
| 12 |
Correct |
13 ms |
12160 KB |
Output is correct |
| 13 |
Correct |
16 ms |
12160 KB |
Output is correct |
| 14 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 15 |
Correct |
11 ms |
12032 KB |
Output is correct |
| 16 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 17 |
Correct |
12 ms |
12288 KB |
Output is correct |
| 18 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 19 |
Correct |
12 ms |
12132 KB |
Output is correct |
| 20 |
Correct |
12 ms |
12160 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 2 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 3 |
Correct |
14 ms |
12160 KB |
Output is correct |
| 4 |
Correct |
13 ms |
12032 KB |
Output is correct |
| 5 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 6 |
Correct |
13 ms |
12160 KB |
Output is correct |
| 7 |
Correct |
13 ms |
12160 KB |
Output is correct |
| 8 |
Correct |
11 ms |
12028 KB |
Output is correct |
| 9 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 10 |
Correct |
11 ms |
12032 KB |
Output is correct |
| 11 |
Correct |
11 ms |
12032 KB |
Output is correct |
| 12 |
Correct |
13 ms |
12160 KB |
Output is correct |
| 13 |
Correct |
16 ms |
12160 KB |
Output is correct |
| 14 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 15 |
Correct |
11 ms |
12032 KB |
Output is correct |
| 16 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 17 |
Correct |
12 ms |
12288 KB |
Output is correct |
| 18 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 19 |
Correct |
12 ms |
12132 KB |
Output is correct |
| 20 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 21 |
Correct |
11 ms |
12032 KB |
Output is correct |
| 22 |
Correct |
12 ms |
12208 KB |
Output is correct |
| 23 |
Correct |
13 ms |
12160 KB |
Output is correct |
| 24 |
Correct |
17 ms |
12160 KB |
Output is correct |
| 25 |
Correct |
13 ms |
12288 KB |
Output is correct |
| 26 |
Correct |
13 ms |
12220 KB |
Output is correct |
| 27 |
Correct |
13 ms |
12160 KB |
Output is correct |
| 28 |
Correct |
13 ms |
12288 KB |
Output is correct |
| 29 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 30 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 31 |
Correct |
13 ms |
12288 KB |
Output is correct |
| 32 |
Correct |
13 ms |
12160 KB |
Output is correct |
| 33 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 34 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 35 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 36 |
Correct |
11 ms |
12032 KB |
Output is correct |
| 37 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 38 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 39 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 40 |
Correct |
11 ms |
12032 KB |
Output is correct |
| 41 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 42 |
Correct |
11 ms |
12160 KB |
Output is correct |
| 43 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 44 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 45 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 46 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 47 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 48 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 49 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 50 |
Correct |
11 ms |
12032 KB |
Output is correct |
| 51 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 52 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 53 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 54 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 55 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 56 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 57 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 58 |
Correct |
12 ms |
12160 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 2 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 3 |
Correct |
14 ms |
12160 KB |
Output is correct |
| 4 |
Correct |
13 ms |
12032 KB |
Output is correct |
| 5 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 6 |
Correct |
13 ms |
12160 KB |
Output is correct |
| 7 |
Correct |
13 ms |
12160 KB |
Output is correct |
| 8 |
Correct |
11 ms |
12028 KB |
Output is correct |
| 9 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 10 |
Correct |
11 ms |
12032 KB |
Output is correct |
| 11 |
Correct |
11 ms |
12032 KB |
Output is correct |
| 12 |
Correct |
13 ms |
12160 KB |
Output is correct |
| 13 |
Correct |
16 ms |
12160 KB |
Output is correct |
| 14 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 15 |
Correct |
11 ms |
12032 KB |
Output is correct |
| 16 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 17 |
Correct |
12 ms |
12288 KB |
Output is correct |
| 18 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 19 |
Correct |
12 ms |
12132 KB |
Output is correct |
| 20 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 21 |
Correct |
11 ms |
12032 KB |
Output is correct |
| 22 |
Correct |
12 ms |
12208 KB |
Output is correct |
| 23 |
Correct |
13 ms |
12160 KB |
Output is correct |
| 24 |
Correct |
17 ms |
12160 KB |
Output is correct |
| 25 |
Correct |
13 ms |
12288 KB |
Output is correct |
| 26 |
Correct |
13 ms |
12220 KB |
Output is correct |
| 27 |
Correct |
13 ms |
12160 KB |
Output is correct |
| 28 |
Correct |
13 ms |
12288 KB |
Output is correct |
| 29 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 30 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 31 |
Correct |
13 ms |
12288 KB |
Output is correct |
| 32 |
Correct |
13 ms |
12160 KB |
Output is correct |
| 33 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 34 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 35 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 36 |
Correct |
11 ms |
12032 KB |
Output is correct |
| 37 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 38 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 39 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 40 |
Correct |
11 ms |
12032 KB |
Output is correct |
| 41 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 42 |
Correct |
11 ms |
12160 KB |
Output is correct |
| 43 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 44 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 45 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 46 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 47 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 48 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 49 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 50 |
Correct |
11 ms |
12032 KB |
Output is correct |
| 51 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 52 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 53 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 54 |
Correct |
12 ms |
12032 KB |
Output is correct |
| 55 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 56 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 57 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 58 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 59 |
Correct |
456 ms |
37972 KB |
Output is correct |
| 60 |
Correct |
563 ms |
40856 KB |
Output is correct |
| 61 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 62 |
Correct |
12 ms |
12160 KB |
Output is correct |
| 63 |
Correct |
433 ms |
35252 KB |
Output is correct |
| 64 |
Correct |
16 ms |
12544 KB |
Output is correct |
| 65 |
Correct |
24 ms |
14080 KB |
Output is correct |
| 66 |
Correct |
218 ms |
28792 KB |
Output is correct |
| 67 |
Correct |
626 ms |
49056 KB |
Output is correct |
| 68 |
Correct |
632 ms |
49956 KB |
Output is correct |
| 69 |
Correct |
20 ms |
13056 KB |
Output is correct |
| 70 |
Correct |
116 ms |
21996 KB |
Output is correct |
| 71 |
Correct |
374 ms |
43868 KB |
Output is correct |
| 72 |
Correct |
437 ms |
42852 KB |
Output is correct |
| 73 |
Correct |
123 ms |
19700 KB |
Output is correct |
| 74 |
Correct |
538 ms |
39672 KB |
Output is correct |
| 75 |
Correct |
39 ms |
15608 KB |
Output is correct |
| 76 |
Correct |
392 ms |
43604 KB |
Output is correct |
| 77 |
Correct |
385 ms |
43532 KB |
Output is correct |
| 78 |
Correct |
38 ms |
15688 KB |
Output is correct |
| 79 |
Correct |
589 ms |
47172 KB |
Output is correct |
| 80 |
Correct |
15 ms |
12388 KB |
Output is correct |
| 81 |
Correct |
130 ms |
22000 KB |
Output is correct |
| 82 |
Correct |
484 ms |
41580 KB |
Output is correct |
| 83 |
Correct |
588 ms |
39668 KB |
Output is correct |
| 84 |
Correct |
541 ms |
39784 KB |
Output is correct |
| 85 |
Correct |
535 ms |
39788 KB |
Output is correct |
| 86 |
Correct |
527 ms |
40780 KB |
Output is correct |
| 87 |
Correct |
597 ms |
40788 KB |
Output is correct |
