| # |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
| 959609 |
2024-04-08T13:42:51 Z |
Blagoj |
Network (BOI15_net) |
C++17 |
|
376 ms |
57968 KB |
#include <bits/stdc++.h>
using namespace std;
#define endl '\n'
#define ll long long
#define all(x) (x).begin(), (x).end()
const int mxn = 5e5 + 10;
vector<int> g[mxn], leafs;
void dfs(int cur, int par) {
bool leaf = 1;
for (auto x : g[cur]) {
if (x == par) continue;
leaf = 0;
dfs(x, cur);
}
if (leaf) leafs.push_back(cur);
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int n;
cin >> n;
for (int i = 0; i < n - 1; i++) {
int f, t;
cin >> f >> t;
g[f].push_back(t);
g[t].push_back(f);
}
int root;
for (int i = 1; i <= n; i++) if (g[i].size() >= 2) root = i;
dfs(root, root);
int sz = leafs.size();
vector<pair<int, int>> v;
for (int i = 0; i < sz / 2; i++) v.push_back({leafs[i], leafs[i + sz / 2]});
if (sz % 2 != 0) v.push_back({leafs[0], leafs.back()});
cout << v.size() << endl;
for (auto x : v) cout << x.first << " " << x.second << endl;
}
Compilation message
net.cpp: In function 'int main()':
net.cpp:36:8: warning: 'root' may be used uninitialized in this function [-Wmaybe-uninitialized]
36 | dfs(root, root);
| ~~~^~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 2 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 3 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 4 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 5 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 6 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 7 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 8 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 9 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 10 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 11 |
Correct |
3 ms |
12144 KB |
Output is correct |
| 12 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 13 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 14 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 15 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 16 |
Correct |
3 ms |
12136 KB |
Output is correct |
| 17 |
Correct |
3 ms |
12200 KB |
Output is correct |
| 18 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 19 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 20 |
Correct |
3 ms |
12200 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 2 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 3 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 4 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 5 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 6 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 7 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 8 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 9 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 10 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 11 |
Correct |
3 ms |
12144 KB |
Output is correct |
| 12 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 13 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 14 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 15 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 16 |
Correct |
3 ms |
12136 KB |
Output is correct |
| 17 |
Correct |
3 ms |
12200 KB |
Output is correct |
| 18 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 19 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 20 |
Correct |
3 ms |
12200 KB |
Output is correct |
| 21 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 22 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 23 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 24 |
Correct |
4 ms |
12132 KB |
Output is correct |
| 25 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 26 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 27 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 28 |
Correct |
4 ms |
12208 KB |
Output is correct |
| 29 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 30 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 31 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 32 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 33 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 34 |
Correct |
3 ms |
12200 KB |
Output is correct |
| 35 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 36 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 37 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 38 |
Correct |
4 ms |
12120 KB |
Output is correct |
| 39 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 40 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 41 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 42 |
Correct |
4 ms |
12196 KB |
Output is correct |
| 43 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 44 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 45 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 46 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 47 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 48 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 49 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 50 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 51 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 52 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 53 |
Correct |
4 ms |
12256 KB |
Output is correct |
| 54 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 55 |
Correct |
4 ms |
12120 KB |
Output is correct |
| 56 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 57 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 58 |
Correct |
4 ms |
12120 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 2 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 3 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 4 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 5 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 6 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 7 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 8 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 9 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 10 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 11 |
Correct |
3 ms |
12144 KB |
Output is correct |
| 12 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 13 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 14 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 15 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 16 |
Correct |
3 ms |
12136 KB |
Output is correct |
| 17 |
Correct |
3 ms |
12200 KB |
Output is correct |
| 18 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 19 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 20 |
Correct |
3 ms |
12200 KB |
Output is correct |
| 21 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 22 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 23 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 24 |
Correct |
4 ms |
12132 KB |
Output is correct |
| 25 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 26 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 27 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 28 |
Correct |
4 ms |
12208 KB |
Output is correct |
| 29 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 30 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 31 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 32 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 33 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 34 |
Correct |
3 ms |
12200 KB |
Output is correct |
| 35 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 36 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 37 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 38 |
Correct |
4 ms |
12120 KB |
Output is correct |
| 39 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 40 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 41 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 42 |
Correct |
4 ms |
12196 KB |
Output is correct |
| 43 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 44 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 45 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 46 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 47 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 48 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 49 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 50 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 51 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 52 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 53 |
Correct |
4 ms |
12256 KB |
Output is correct |
| 54 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 55 |
Correct |
4 ms |
12120 KB |
Output is correct |
| 56 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 57 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 58 |
Correct |
4 ms |
12120 KB |
Output is correct |
| 59 |
Correct |
301 ms |
37244 KB |
Output is correct |
| 60 |
Correct |
275 ms |
40068 KB |
Output is correct |
| 61 |
Correct |
3 ms |
12204 KB |
Output is correct |
| 62 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 63 |
Correct |
191 ms |
34760 KB |
Output is correct |
| 64 |
Correct |
4 ms |
12376 KB |
Output is correct |
| 65 |
Correct |
9 ms |
13916 KB |
Output is correct |
| 66 |
Correct |
87 ms |
25076 KB |
Output is correct |
| 67 |
Correct |
340 ms |
57968 KB |
Output is correct |
| 68 |
Correct |
327 ms |
51028 KB |
Output is correct |
| 69 |
Correct |
7 ms |
12980 KB |
Output is correct |
| 70 |
Correct |
53 ms |
21880 KB |
Output is correct |
| 71 |
Correct |
202 ms |
44004 KB |
Output is correct |
| 72 |
Correct |
215 ms |
42584 KB |
Output is correct |
| 73 |
Correct |
48 ms |
19412 KB |
Output is correct |
| 74 |
Correct |
275 ms |
38920 KB |
Output is correct |
| 75 |
Correct |
19 ms |
15448 KB |
Output is correct |
| 76 |
Correct |
206 ms |
43696 KB |
Output is correct |
| 77 |
Correct |
219 ms |
43668 KB |
Output is correct |
| 78 |
Correct |
18 ms |
15536 KB |
Output is correct |
| 79 |
Correct |
306 ms |
44960 KB |
Output is correct |
| 80 |
Correct |
4 ms |
12380 KB |
Output is correct |
| 81 |
Correct |
52 ms |
21960 KB |
Output is correct |
| 82 |
Correct |
244 ms |
41036 KB |
Output is correct |
| 83 |
Correct |
376 ms |
38780 KB |
Output is correct |
| 84 |
Correct |
284 ms |
38672 KB |
Output is correct |
| 85 |
Correct |
304 ms |
38816 KB |
Output is correct |
| 86 |
Correct |
300 ms |
40132 KB |
Output is correct |
| 87 |
Correct |
294 ms |
40376 KB |
Output is correct |
