| # |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
| 545716 |
2022-04-05T09:13:03 Z |
SavicS |
Network (BOI15_net) |
C++17 |
|
476 ms |
43780 KB |
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <bits/stdc++.h>
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef pair<ld,ld> pdd;
#define ff(i,a,b) for(int i = a; i <= b; i++)
#define fb(i,b,a) for(int i = b; i >= a; i--)
#define trav(a,x) for (auto& a : x)
#define sz(a) (int)(a).size()
#define pb push_back
#define fi first
#define se second
#define lb lower_bound
#define ub upper_bound
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
template<typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
// os.order_of_key(k) the number of elements in the os less than k
// *os.find_by_order(k) print the k-th smallest number in os(0-based)
const int mod = 998244353;
const int inf = 1e9 + 5;
const int mxN = 500005;
int n;
vector<int> g[mxN];
int timer = 0;
int in[mxN];
void dfs(int v, int p){
in[v] = ++timer;
for(auto u : g[v]){
if(u != p){
dfs(u, v);
}
}
}
bool cmp(int s1, int s2){
return in[s1] < in[s2];
}
int main() {
cin.tie(0)->sync_with_stdio(0);
cin >> n;
ff(i,1,n - 1){
int u, v;
cin >> u >> v;
g[u].pb(v);
g[v].pb(u);
}
if(n == 1){
cout << 1 << '\n';
cout << 1 << " " << 1 << '\n';
return 0;
}
dfs(1, -1);
vector<int> leaf;
ff(i,1,n)if(sz(g[i]) == 1)leaf.pb(i);
sort(all(leaf), cmp);
cout << (sz(leaf) + 1) / 2 << '\n';
if(sz(leaf) % 2 == 1){
cout << leaf[0] << " " << leaf.back() << '\n';
leaf.pop_back();
}
int K = sz(leaf) / 2;
for(int i = 0; i + K < sz(leaf); i++){
cout << leaf[i] << " " << leaf[i + K] << '\n';
}
return 0;
}
/*
// probati bojenje sahovski
*/
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
7 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 |
9 ms |
11988 KB |
Output is correct |
| 9 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 10 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 11 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 12 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 13 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 14 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 15 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 16 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 17 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 18 |
Correct |
7 ms |
12040 KB |
Output is correct |
| 19 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 20 |
Correct |
6 ms |
12068 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
7 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 |
9 ms |
11988 KB |
Output is correct |
| 9 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 10 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 11 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 12 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 13 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 14 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 15 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 16 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 17 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 18 |
Correct |
7 ms |
12040 KB |
Output is correct |
| 19 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 20 |
Correct |
6 ms |
12068 KB |
Output is correct |
| 21 |
Correct |
8 ms |
12116 KB |
Output is correct |
| 22 |
Correct |
9 ms |
12116 KB |
Output is correct |
| 23 |
Correct |
8 ms |
12096 KB |
Output is correct |
| 24 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 25 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 26 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 27 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 28 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 29 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 30 |
Correct |
7 ms |
11964 KB |
Output is correct |
| 31 |
Correct |
8 ms |
12168 KB |
Output is correct |
| 32 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 33 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 34 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 35 |
Correct |
7 ms |
12072 KB |
Output is correct |
| 36 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 37 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 38 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 39 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 40 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 41 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 42 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 43 |
Correct |
6 ms |
12116 KB |
Output is correct |
| 44 |
Correct |
8 ms |
12068 KB |
Output is correct |
| 45 |
Correct |
7 ms |
11972 KB |
Output is correct |
| 46 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 47 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 48 |
Correct |
8 ms |
12044 KB |
Output is correct |
| 49 |
Correct |
7 ms |
12112 KB |
Output is correct |
| 50 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 51 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 52 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 53 |
Correct |
9 ms |
12072 KB |
Output is correct |
| 54 |
Correct |
7 ms |
12028 KB |
Output is correct |
| 55 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 56 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 57 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 58 |
Correct |
7 ms |
12116 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
7 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 |
9 ms |
11988 KB |
Output is correct |
| 9 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 10 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 11 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 12 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 13 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 14 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 15 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 16 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 17 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 18 |
Correct |
7 ms |
12040 KB |
Output is correct |
| 19 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 20 |
Correct |
6 ms |
12068 KB |
Output is correct |
| 21 |
Correct |
8 ms |
12116 KB |
Output is correct |
| 22 |
Correct |
9 ms |
12116 KB |
Output is correct |
| 23 |
Correct |
8 ms |
12096 KB |
Output is correct |
| 24 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 25 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 26 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 27 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 28 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 29 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 30 |
Correct |
7 ms |
11964 KB |
Output is correct |
| 31 |
Correct |
8 ms |
12168 KB |
Output is correct |
| 32 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 33 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 34 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 35 |
Correct |
7 ms |
12072 KB |
Output is correct |
| 36 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 37 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 38 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 39 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 40 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 41 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 42 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 43 |
Correct |
6 ms |
12116 KB |
Output is correct |
| 44 |
Correct |
8 ms |
12068 KB |
Output is correct |
| 45 |
Correct |
7 ms |
11972 KB |
Output is correct |
| 46 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 47 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 48 |
Correct |
8 ms |
12044 KB |
Output is correct |
| 49 |
Correct |
7 ms |
12112 KB |
Output is correct |
| 50 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 51 |
Correct |
6 ms |
11988 KB |
Output is correct |
| 52 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 53 |
Correct |
9 ms |
12072 KB |
Output is correct |
| 54 |
Correct |
7 ms |
12028 KB |
Output is correct |
| 55 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 56 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 57 |
Correct |
7 ms |
11988 KB |
Output is correct |
| 58 |
Correct |
7 ms |
12116 KB |
Output is correct |
| 59 |
Correct |
343 ms |
37840 KB |
Output is correct |
| 60 |
Correct |
421 ms |
40720 KB |
Output is correct |
| 61 |
Correct |
7 ms |
12064 KB |
Output is correct |
| 62 |
Correct |
8 ms |
11988 KB |
Output is correct |
| 63 |
Correct |
364 ms |
35164 KB |
Output is correct |
| 64 |
Correct |
8 ms |
12372 KB |
Output is correct |
| 65 |
Correct |
15 ms |
13512 KB |
Output is correct |
| 66 |
Correct |
132 ms |
24476 KB |
Output is correct |
| 67 |
Correct |
432 ms |
42264 KB |
Output is correct |
| 68 |
Correct |
476 ms |
42972 KB |
Output is correct |
| 69 |
Correct |
14 ms |
12988 KB |
Output is correct |
| 70 |
Correct |
104 ms |
21836 KB |
Output is correct |
| 71 |
Correct |
335 ms |
43780 KB |
Output is correct |
| 72 |
Correct |
373 ms |
42608 KB |
Output is correct |
| 73 |
Correct |
95 ms |
19660 KB |
Output is correct |
| 74 |
Correct |
463 ms |
39612 KB |
Output is correct |
| 75 |
Correct |
32 ms |
15512 KB |
Output is correct |
| 76 |
Correct |
359 ms |
43536 KB |
Output is correct |
| 77 |
Correct |
332 ms |
43556 KB |
Output is correct |
| 78 |
Correct |
27 ms |
15132 KB |
Output is correct |
| 79 |
Correct |
437 ms |
41496 KB |
Output is correct |
| 80 |
Correct |
8 ms |
12244 KB |
Output is correct |
| 81 |
Correct |
124 ms |
21996 KB |
Output is correct |
| 82 |
Correct |
392 ms |
41388 KB |
Output is correct |
| 83 |
Correct |
445 ms |
39576 KB |
Output is correct |
| 84 |
Correct |
427 ms |
39604 KB |
Output is correct |
| 85 |
Correct |
435 ms |
39612 KB |
Output is correct |
| 86 |
Correct |
470 ms |
40672 KB |
Output is correct |
| 87 |
Correct |
415 ms |
40636 KB |
Output is correct |
