| # |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
| 984971 |
2024-05-17T08:51:11 Z |
steveonalex |
Network (BOI15_net) |
C++17 |
|
379 ms |
57756 KB |
#include <bits/stdc++.h>
// #include "roads.h"
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
#define ALL(v) (v).begin(), (v).end()
#define MASK(i) (1LL << (i))
#define GETBIT(mask, i) (((mask) >> (i)) & 1)
// mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rng(1);
ll rngesus(ll l, ll r){return ((ull) rng()) % (r - l + 1) + l;}
ll max(ll a, ll b){return (a > b) ? a : b;}
ll min(ll a, ll b){return (a < b) ? a : b;}
ll LASTBIT(ll mask){return mask & (-mask);}
ll pop_cnt(ll mask){return __builtin_popcountll(mask);}
ll ctz(ll mask){return __builtin_ctzll(mask);}
ll clz(ll mask){return __builtin_clzll(mask);}
ll logOf(ll mask){return 63 - clz(mask);}
template <class T1, class T2>
bool minimize(T1 &a, T2 b){
if (a > b){a = b; return true;}
return false;
}
template <class T1, class T2>
bool maximize(T1 &a, T2 b){
if (a < b){a = b; return true;}
return false;
}
template <class T>
void printArr(T a, string separator = " ", string finish = "\n", ostream& out = cout){
for(auto i: a) out << i << separator;
out << finish;
}
template <class T>
void remove_dup(vector<T> &a){
sort(ALL(a));
a.resize(unique(ALL(a)) - a.begin());
}
const int N = 5e5 + 69;
int n;
vector<int> graph[N];
vector<int> ans;
void dfs(int u, int p){
if (graph[u].size() == 1) ans.push_back(u);
for(int v: graph[u]) if (v != p){
dfs(v, u);
}
}
int main(void){
ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> n;
for(int i = 1; i<n; ++i) {
int u, v; cin >> u >> v;
graph[u].push_back(v);
graph[v].push_back(u);
}
int root = 0;
for(int i = 1; i<=n; ++i) if (graph[i].size() > 1) root = i;
dfs(root, root);
int res = (ans.size() + 1) / 2;
cout << res << "\n";
for(int i = 0; i<res; ++i) cout << ans[i] << " " << ans[i + ans.size() / 2] << "\n";
return 0;
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
4 ms |
12120 KB |
Output is correct |
| 2 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 3 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 4 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 5 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 6 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 7 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 8 |
Correct |
3 ms |
12048 KB |
Output is correct |
| 9 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 10 |
Correct |
3 ms |
12144 KB |
Output is correct |
| 11 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 12 |
Correct |
4 ms |
12120 KB |
Output is correct |
| 13 |
Correct |
3 ms |
12120 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 |
12124 KB |
Output is correct |
| 17 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 18 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 19 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 20 |
Correct |
3 ms |
12124 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
4 ms |
12120 KB |
Output is correct |
| 2 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 3 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 4 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 5 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 6 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 7 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 8 |
Correct |
3 ms |
12048 KB |
Output is correct |
| 9 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 10 |
Correct |
3 ms |
12144 KB |
Output is correct |
| 11 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 12 |
Correct |
4 ms |
12120 KB |
Output is correct |
| 13 |
Correct |
3 ms |
12120 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 |
12124 KB |
Output is correct |
| 17 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 18 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 19 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 20 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 21 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 22 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 23 |
Correct |
4 ms |
12120 KB |
Output is correct |
| 24 |
Correct |
5 ms |
12284 KB |
Output is correct |
| 25 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 26 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 27 |
Correct |
5 ms |
12212 KB |
Output is correct |
| 28 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 29 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 30 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 31 |
Correct |
4 ms |
12212 KB |
Output is correct |
| 32 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 33 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 34 |
Correct |
4 ms |
12124 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 |
3 ms |
12124 KB |
Output is correct |
| 39 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 40 |
Correct |
3 ms |
12140 KB |
Output is correct |
| 41 |
Correct |
4 ms |
12288 KB |
Output is correct |
| 42 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 43 |
Correct |
4 ms |
12128 KB |
Output is correct |
| 44 |
Correct |
4 ms |
12128 KB |
Output is correct |
| 45 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 46 |
Correct |
4 ms |
12212 KB |
Output is correct |
| 47 |
Correct |
4 ms |
12204 KB |
Output is correct |
| 48 |
Correct |
3 ms |
12224 KB |
Output is correct |
| 49 |
Correct |
4 ms |
12216 KB |
Output is correct |
| 50 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 51 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 52 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 53 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 54 |
Correct |
3 ms |
12144 KB |
Output is correct |
| 55 |
Correct |
4 ms |
12224 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 |
12264 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
4 ms |
12120 KB |
Output is correct |
| 2 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 3 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 4 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 5 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 6 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 7 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 8 |
Correct |
3 ms |
12048 KB |
Output is correct |
| 9 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 10 |
Correct |
3 ms |
12144 KB |
Output is correct |
| 11 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 12 |
Correct |
4 ms |
12120 KB |
Output is correct |
| 13 |
Correct |
3 ms |
12120 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 |
12124 KB |
Output is correct |
| 17 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 18 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 19 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 20 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 21 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 22 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 23 |
Correct |
4 ms |
12120 KB |
Output is correct |
| 24 |
Correct |
5 ms |
12284 KB |
Output is correct |
| 25 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 26 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 27 |
Correct |
5 ms |
12212 KB |
Output is correct |
| 28 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 29 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 30 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 31 |
Correct |
4 ms |
12212 KB |
Output is correct |
| 32 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 33 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 34 |
Correct |
4 ms |
12124 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 |
3 ms |
12124 KB |
Output is correct |
| 39 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 40 |
Correct |
3 ms |
12140 KB |
Output is correct |
| 41 |
Correct |
4 ms |
12288 KB |
Output is correct |
| 42 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 43 |
Correct |
4 ms |
12128 KB |
Output is correct |
| 44 |
Correct |
4 ms |
12128 KB |
Output is correct |
| 45 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 46 |
Correct |
4 ms |
12212 KB |
Output is correct |
| 47 |
Correct |
4 ms |
12204 KB |
Output is correct |
| 48 |
Correct |
3 ms |
12224 KB |
Output is correct |
| 49 |
Correct |
4 ms |
12216 KB |
Output is correct |
| 50 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 51 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 52 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 53 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 54 |
Correct |
3 ms |
12144 KB |
Output is correct |
| 55 |
Correct |
4 ms |
12224 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 |
12264 KB |
Output is correct |
| 59 |
Correct |
249 ms |
35952 KB |
Output is correct |
| 60 |
Correct |
307 ms |
38800 KB |
Output is correct |
| 61 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 62 |
Correct |
3 ms |
12152 KB |
Output is correct |
| 63 |
Correct |
217 ms |
33668 KB |
Output is correct |
| 64 |
Correct |
5 ms |
12348 KB |
Output is correct |
| 65 |
Correct |
10 ms |
13688 KB |
Output is correct |
| 66 |
Correct |
111 ms |
25140 KB |
Output is correct |
| 67 |
Correct |
379 ms |
57756 KB |
Output is correct |
| 68 |
Correct |
350 ms |
50712 KB |
Output is correct |
| 69 |
Correct |
7 ms |
12892 KB |
Output is correct |
| 70 |
Correct |
51 ms |
21320 KB |
Output is correct |
| 71 |
Correct |
182 ms |
42048 KB |
Output is correct |
| 72 |
Correct |
216 ms |
40784 KB |
Output is correct |
| 73 |
Correct |
44 ms |
19152 KB |
Output is correct |
| 74 |
Correct |
273 ms |
37628 KB |
Output is correct |
| 75 |
Correct |
17 ms |
15320 KB |
Output is correct |
| 76 |
Correct |
220 ms |
41680 KB |
Output is correct |
| 77 |
Correct |
186 ms |
41644 KB |
Output is correct |
| 78 |
Correct |
22 ms |
15440 KB |
Output is correct |
| 79 |
Correct |
303 ms |
45096 KB |
Output is correct |
| 80 |
Correct |
4 ms |
12380 KB |
Output is correct |
| 81 |
Correct |
53 ms |
21372 KB |
Output is correct |
| 82 |
Correct |
235 ms |
39876 KB |
Output is correct |
| 83 |
Correct |
260 ms |
37736 KB |
Output is correct |
| 84 |
Correct |
255 ms |
37828 KB |
Output is correct |
| 85 |
Correct |
273 ms |
37660 KB |
Output is correct |
| 86 |
Correct |
274 ms |
38708 KB |
Output is correct |
| 87 |
Correct |
295 ms |
38764 KB |
Output is correct |
