| # |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
| 965449 |
2024-04-18T15:10:14 Z |
pcc |
Network (BOI15_net) |
C++17 |
|
342 ms |
49804 KB |
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pll pair<ll,ll>
#define pii pair<int,int>
#define fs first
#define sc second
#define tlll tuple<ll,ll,ll>
const int mxn = 5e5+10;
vector<int> tree[mxn];
int dfn[mxn],pt;
int N;
vector<pii> ans;
void dfs(int now,int par){
dfn[now] = ++pt;
for(auto nxt:tree[now]){
if(nxt == par)continue;
dfs(nxt,now);
}
return;
}
int main(){
ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
cin>>N;
for(int i = 1;i<N;i++){
int a,b;
cin>>a>>b;
tree[a].push_back(b);
tree[b].push_back(a);
}
dfs(1,1);
vector<pii> v;
for(int i = 1;i<=N;i++){
if(tree[i].size() == 1)v.push_back(pii(dfn[i],i));
}
sort(v.begin(),v.end());
for(int i = 0;i<v.size()/2;i++){
ans.push_back(pii(v[i].sc,v[i+v.size()/2].sc));
}
if(v.size()&1)ans.push_back(pii(v.back().sc,v[0].sc));
cout<<ans.size()<<'\n';
for(auto &i:ans)cout<<i.fs<<' '<<i.sc<<'\n';
return 0;
}
Compilation message
net.cpp: In function 'int main()':
net.cpp:43:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
43 | for(int i = 0;i<v.size()/2;i++){
| ~^~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 2 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 3 |
Correct |
3 ms |
14168 KB |
Output is correct |
| 4 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 5 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 6 |
Correct |
3 ms |
13912 KB |
Output is correct |
| 7 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 8 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 9 |
Correct |
3 ms |
13912 KB |
Output is correct |
| 10 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 11 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 12 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 13 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 14 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 15 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 16 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 17 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 18 |
Correct |
3 ms |
13912 KB |
Output is correct |
| 19 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 20 |
Correct |
3 ms |
13916 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 2 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 3 |
Correct |
3 ms |
14168 KB |
Output is correct |
| 4 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 5 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 6 |
Correct |
3 ms |
13912 KB |
Output is correct |
| 7 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 8 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 9 |
Correct |
3 ms |
13912 KB |
Output is correct |
| 10 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 11 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 12 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 13 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 14 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 15 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 16 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 17 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 18 |
Correct |
3 ms |
13912 KB |
Output is correct |
| 19 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 20 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 21 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 22 |
Correct |
4 ms |
14004 KB |
Output is correct |
| 23 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 24 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 25 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 26 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 27 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 28 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 29 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 30 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 31 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 32 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 33 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 34 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 35 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 36 |
Correct |
4 ms |
13980 KB |
Output is correct |
| 37 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 38 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 39 |
Correct |
3 ms |
13912 KB |
Output is correct |
| 40 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 41 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 42 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 43 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 44 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 45 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 46 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 47 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 48 |
Correct |
4 ms |
13912 KB |
Output is correct |
| 49 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 50 |
Correct |
3 ms |
13988 KB |
Output is correct |
| 51 |
Correct |
3 ms |
14168 KB |
Output is correct |
| 52 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 53 |
Correct |
5 ms |
13916 KB |
Output is correct |
| 54 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 55 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 56 |
Correct |
3 ms |
13748 KB |
Output is correct |
| 57 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 58 |
Correct |
4 ms |
13916 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 2 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 3 |
Correct |
3 ms |
14168 KB |
Output is correct |
| 4 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 5 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 6 |
Correct |
3 ms |
13912 KB |
Output is correct |
| 7 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 8 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 9 |
Correct |
3 ms |
13912 KB |
Output is correct |
| 10 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 11 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 12 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 13 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 14 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 15 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 16 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 17 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 18 |
Correct |
3 ms |
13912 KB |
Output is correct |
| 19 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 20 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 21 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 22 |
Correct |
4 ms |
14004 KB |
Output is correct |
| 23 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 24 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 25 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 26 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 27 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 28 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 29 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 30 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 31 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 32 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 33 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 34 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 35 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 36 |
Correct |
4 ms |
13980 KB |
Output is correct |
| 37 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 38 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 39 |
Correct |
3 ms |
13912 KB |
Output is correct |
| 40 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 41 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 42 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 43 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 44 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 45 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 46 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 47 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 48 |
Correct |
4 ms |
13912 KB |
Output is correct |
| 49 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 50 |
Correct |
3 ms |
13988 KB |
Output is correct |
| 51 |
Correct |
3 ms |
14168 KB |
Output is correct |
| 52 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 53 |
Correct |
5 ms |
13916 KB |
Output is correct |
| 54 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 55 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 56 |
Correct |
3 ms |
13748 KB |
Output is correct |
| 57 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 58 |
Correct |
4 ms |
13916 KB |
Output is correct |
| 59 |
Correct |
258 ms |
44252 KB |
Output is correct |
| 60 |
Correct |
309 ms |
46612 KB |
Output is correct |
| 61 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 62 |
Correct |
3 ms |
13916 KB |
Output is correct |
| 63 |
Correct |
226 ms |
40684 KB |
Output is correct |
| 64 |
Correct |
4 ms |
14168 KB |
Output is correct |
| 65 |
Correct |
10 ms |
15384 KB |
Output is correct |
| 66 |
Correct |
80 ms |
26196 KB |
Output is correct |
| 67 |
Correct |
322 ms |
42832 KB |
Output is correct |
| 68 |
Correct |
324 ms |
43992 KB |
Output is correct |
| 69 |
Correct |
12 ms |
14940 KB |
Output is correct |
| 70 |
Correct |
60 ms |
25156 KB |
Output is correct |
| 71 |
Correct |
221 ms |
49804 KB |
Output is correct |
| 72 |
Correct |
248 ms |
48188 KB |
Output is correct |
| 73 |
Correct |
60 ms |
22076 KB |
Output is correct |
| 74 |
Correct |
317 ms |
42460 KB |
Output is correct |
| 75 |
Correct |
22 ms |
17880 KB |
Output is correct |
| 76 |
Correct |
230 ms |
49324 KB |
Output is correct |
| 77 |
Correct |
230 ms |
49532 KB |
Output is correct |
| 78 |
Correct |
26 ms |
16988 KB |
Output is correct |
| 79 |
Correct |
342 ms |
41820 KB |
Output is correct |
| 80 |
Correct |
4 ms |
14168 KB |
Output is correct |
| 81 |
Correct |
70 ms |
24648 KB |
Output is correct |
| 82 |
Correct |
282 ms |
47300 KB |
Output is correct |
| 83 |
Correct |
317 ms |
42460 KB |
Output is correct |
| 84 |
Correct |
300 ms |
42428 KB |
Output is correct |
| 85 |
Correct |
310 ms |
42448 KB |
Output is correct |
| 86 |
Correct |
286 ms |
45212 KB |
Output is correct |
| 87 |
Correct |
307 ms |
45960 KB |
Output is correct |
