| # |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
| 849777 |
2023-09-15T10:43:18 Z |
Vanilla |
Network (BOI15_net) |
C++17 |
|
316 ms |
36812 KB |
#include <bits/stdc++.h>
#include <fstream>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
using namespace std;
template<class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
struct custom_hash {static uint64_t splitmix64(uint64_t x) {x += 0x9e3779b97f4a7c15;x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;x = (x ^ (x >> 27)) * 0x94d049bb133111eb;return x ^ (x >> 31);}size_t operator()(uint64_t x) const {static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();return splitmix64(x + FIXED_RANDOM);}};
// string __fname = ""; ifstream in (__fname + ".in"); ofstream out (__fname + ".out");
// #define cin in
// #define cout out
#define int64 long long
#define uint64 unsigned long long
#define x first
#define y second
#define pb push_back
#define pii pair <int, int>
#define pii64 pair <int64, int64>
#define db(x) cout << "> " << #x << ": " << (x) << "\n"
#define qr queries()
#define yn(x) if (x) {ctn("Yes");}else {ctn("No");}
void solve(int);
void queries(){int n;cin >> n;for (int i = 1; i <= n; i++) solve(i);}
template<class T>T ceildiv(T a, T b) {return a / b + !!(a % b);}
template<class T>T gcd (T a, T b){return (b ? gcd(b, a % b): a);}
template<class T>T lcm (T a, T b){return a * b / gcd(a, b);}
// // // // // // // // // // // // // // // // // // // // // //
/* TEMPLATE - VANILLA */
// // // // // // // // // // // // // // // // // // // // // //
const int ddx[] = {-1, -1, 0, 1, 1, 1, 0, -1};
const int ddy[] = {0, 1, 1, 1, 0, -1, -1, -1};
const int dx[] = {-1, 0, 1, 0};
const int dy[] = {0, 1, 0, -1};
const double pi = 3.14159265359;
const double eps = 1e-6;
const int64 hash_inv = 940594066;
const int64 hash_p = 101;
const int64 mod = 1e9 + 7;
const int maxn = 5e5 + 2;
vector <int> ad[maxn];
void solve(int id){
int n;
cin >> n;
for (int i = 0; i < n - 1; i++){
int a,b;
cin >> a >> b;
ad[a].push_back(b);
ad[b].push_back(a);
}
vector <int> lf;
auto dfs = [&] (auto dfs, int u, int p = -1) -> void {
// cerr << u << " " << p << "\n";
if (ad[u].size() == 1) lf.push_back(u);
for (int v: ad[u]) {
if (v == p) continue;
dfs(dfs, v, u);
}
};
dfs(dfs, 1);
int k = lf.size();
cout << (k + 1) / 2 << "\n";
for (int i = 0; i < k / 2; i++){
cout << lf[i] << " " << lf[k / 2 + i] << "\n";
}
if (k % 2) cout << lf[0] << " " << lf[k - 1] << "\n";
return;
}
int main(){
ios_base::sync_with_stdio(0); cin.tie(0); cout << fixed; cout << setprecision(10);
solve(1);
return 0;
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 2 |
Correct |
3 ms |
12376 KB |
Output is correct |
| 3 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 4 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 5 |
Correct |
3 ms |
12124 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 |
12124 KB |
Output is correct |
| 9 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 10 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 11 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 12 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 13 |
Correct |
3 ms |
12188 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 |
3 ms |
12124 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 |
12124 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 2 |
Correct |
3 ms |
12376 KB |
Output is correct |
| 3 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 4 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 5 |
Correct |
3 ms |
12124 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 |
12124 KB |
Output is correct |
| 9 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 10 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 11 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 12 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 13 |
Correct |
3 ms |
12188 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 |
3 ms |
12124 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 |
12124 KB |
Output is correct |
| 21 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 22 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 23 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 24 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 25 |
Correct |
3 ms |
12136 KB |
Output is correct |
| 26 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 27 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 28 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 29 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 30 |
Correct |
3 ms |
12276 KB |
Output is correct |
| 31 |
Correct |
3 ms |
12112 KB |
Output is correct |
| 32 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 33 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 34 |
Correct |
3 ms |
12144 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 |
12120 KB |
Output is correct |
| 39 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 40 |
Correct |
3 ms |
12128 KB |
Output is correct |
| 41 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 42 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 43 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 44 |
Correct |
3 ms |
12124 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 |
3 ms |
12124 KB |
Output is correct |
| 50 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 51 |
Correct |
3 ms |
12120 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 |
12124 KB |
Output is correct |
| 55 |
Correct |
3 ms |
12124 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 |
12124 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 2 |
Correct |
3 ms |
12376 KB |
Output is correct |
| 3 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 4 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 5 |
Correct |
3 ms |
12124 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 |
12124 KB |
Output is correct |
| 9 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 10 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 11 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 12 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 13 |
Correct |
3 ms |
12188 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 |
3 ms |
12124 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 |
12124 KB |
Output is correct |
| 21 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 22 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 23 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 24 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 25 |
Correct |
3 ms |
12136 KB |
Output is correct |
| 26 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 27 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 28 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 29 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 30 |
Correct |
3 ms |
12276 KB |
Output is correct |
| 31 |
Correct |
3 ms |
12112 KB |
Output is correct |
| 32 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 33 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 34 |
Correct |
3 ms |
12144 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 |
12120 KB |
Output is correct |
| 39 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 40 |
Correct |
3 ms |
12128 KB |
Output is correct |
| 41 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 42 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 43 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 44 |
Correct |
3 ms |
12124 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 |
3 ms |
12124 KB |
Output is correct |
| 50 |
Correct |
3 ms |
12124 KB |
Output is correct |
| 51 |
Correct |
3 ms |
12120 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 |
12124 KB |
Output is correct |
| 55 |
Correct |
3 ms |
12124 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 |
12124 KB |
Output is correct |
| 59 |
Correct |
191 ms |
30024 KB |
Output is correct |
| 60 |
Correct |
236 ms |
32076 KB |
Output is correct |
| 61 |
Correct |
4 ms |
12124 KB |
Output is correct |
| 62 |
Correct |
3 ms |
12120 KB |
Output is correct |
| 63 |
Correct |
169 ms |
28416 KB |
Output is correct |
| 64 |
Correct |
4 ms |
12380 KB |
Output is correct |
| 65 |
Correct |
9 ms |
13404 KB |
Output is correct |
| 66 |
Correct |
72 ms |
23160 KB |
Output is correct |
| 67 |
Correct |
307 ms |
36176 KB |
Output is correct |
| 68 |
Correct |
301 ms |
36812 KB |
Output is correct |
| 69 |
Correct |
6 ms |
12888 KB |
Output is correct |
| 70 |
Correct |
44 ms |
19316 KB |
Output is correct |
| 71 |
Correct |
156 ms |
35164 KB |
Output is correct |
| 72 |
Correct |
178 ms |
34364 KB |
Output is correct |
| 73 |
Correct |
43 ms |
17360 KB |
Output is correct |
| 74 |
Correct |
271 ms |
31052 KB |
Output is correct |
| 75 |
Correct |
17 ms |
14552 KB |
Output is correct |
| 76 |
Correct |
170 ms |
34780 KB |
Output is correct |
| 77 |
Correct |
210 ms |
35300 KB |
Output is correct |
| 78 |
Correct |
18 ms |
14428 KB |
Output is correct |
| 79 |
Correct |
316 ms |
34824 KB |
Output is correct |
| 80 |
Correct |
4 ms |
12380 KB |
Output is correct |
| 81 |
Correct |
59 ms |
19148 KB |
Output is correct |
| 82 |
Correct |
211 ms |
33220 KB |
Output is correct |
| 83 |
Correct |
264 ms |
31284 KB |
Output is correct |
| 84 |
Correct |
272 ms |
31072 KB |
Output is correct |
| 85 |
Correct |
266 ms |
31076 KB |
Output is correct |
| 86 |
Correct |
241 ms |
32200 KB |
Output is correct |
| 87 |
Correct |
299 ms |
32060 KB |
Output is correct |
