| # |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
| 895967 |
2023-12-31T08:52:08 Z |
thunopro |
Network (BOI15_net) |
C++14 |
|
388 ms |
59724 KB |
#include<bits/stdc++.h>
using namespace std ;
#define ll long long
#define maxn 500009
#define fi first
#define se second
#define pb push_back
#define left id<<1
#define right id<<1|1
#define re exit(0);
#define _lower(x) lower_bound(v.begin(),v.end(),x)-v.begin()+1
const int mod = 1e9+7 ;
const int INF = 1e9 ;
const int LOG = 18 ;
typedef vector<int> vi ;
typedef pair<int,int> pii ;
typedef vector<ll> vl ;
typedef vector<pii> vii ;
void add ( int &a , int b )
{
a += b ;
if ( a < 0 ) a += mod ;
if ( a >= mod ) a -= mod ;
}
template < typename T > void chkmin ( T &a , T b ) { if ( a > b ) a = b ; }
template < typename T > void chkmax ( T &a , T b ) { if ( a < b ) a = b ; }
void rf ()
{
freopen ("bai1.inp","r",stdin) ;
// freopen ("bai1.out","w",stdout) ;
}
int _pow ( int a , int n )
{
if ( n == 0 ) return 1 ;
int res = _pow (a,n/2) ;
if ( n % 2 ) return 1ll*res*res%mod*a%mod ;
else return 1ll*res*res%mod ;
}
int n ;
int deg [maxn] ;
vi adjList [maxn] ;
vi leaves ;
void dfs ( int u , int par = 0 )
{
if ( deg [u] == 1 ) leaves.pb (u) ;
for ( auto v : adjList [u] )
{
if ( v == par ) continue ;
dfs (v,u) ;
}
}
int main ()
{
ios_base::sync_with_stdio(0);
cin.tie(0);cout.tie(0) ;
// rf () ;
cin >> n ;
for ( int i = 1 ; i < n ; i ++ )
{
int u , v ; cin >> u >> v ;
deg [u] ++ , deg [v] ++ ;
adjList [u] . pb (v) ;
adjList [v] . pb (u) ;
}
int root = 0 ;
for ( int i = 1 ; i <= n ; i ++ ) if ( deg [i] > 1 ) root = i ;
dfs (root) ;
int res = (leaves.size()+1)/2 ;
cout << res << "\n" ;
for ( int i = 0 ; i < res ; i ++ )
{
cout << leaves[i] << " " << leaves[i+leaves.size()/2] << "\n" ;
}
}
// range , error , check special , ...
// find key , find key
//'-std=c++11' stay hard
// there is no tomorrow
Compilation message
net.cpp: In function 'void rf()':
net.cpp:34:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
34 | freopen ("bai1.inp","r",stdin) ;
| ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
13052 KB |
Output is correct |
| 2 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 3 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 4 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 5 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 6 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 7 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 8 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 9 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 10 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 11 |
Correct |
3 ms |
12956 KB |
Output is correct |
| 12 |
Correct |
3 ms |
12888 KB |
Output is correct |
| 13 |
Correct |
3 ms |
13144 KB |
Output is correct |
| 14 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 15 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 16 |
Correct |
2 ms |
12888 KB |
Output is correct |
| 17 |
Correct |
3 ms |
12948 KB |
Output is correct |
| 18 |
Correct |
3 ms |
12888 KB |
Output is correct |
| 19 |
Correct |
3 ms |
12888 KB |
Output is correct |
| 20 |
Correct |
3 ms |
12892 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
13052 KB |
Output is correct |
| 2 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 3 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 4 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 5 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 6 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 7 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 8 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 9 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 10 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 11 |
Correct |
3 ms |
12956 KB |
Output is correct |
| 12 |
Correct |
3 ms |
12888 KB |
Output is correct |
| 13 |
Correct |
3 ms |
13144 KB |
Output is correct |
| 14 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 15 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 16 |
Correct |
2 ms |
12888 KB |
Output is correct |
| 17 |
Correct |
3 ms |
12948 KB |
Output is correct |
| 18 |
Correct |
3 ms |
12888 KB |
Output is correct |
| 19 |
Correct |
3 ms |
12888 KB |
Output is correct |
| 20 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 21 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 22 |
Correct |
4 ms |
12892 KB |
Output is correct |
| 23 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 24 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 25 |
Correct |
3 ms |
12960 KB |
Output is correct |
| 26 |
Correct |
4 ms |
12892 KB |
Output is correct |
| 27 |
Correct |
4 ms |
12892 KB |
Output is correct |
| 28 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 29 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 30 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 31 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 32 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 33 |
Correct |
2 ms |
13144 KB |
Output is correct |
| 34 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 35 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 36 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 37 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 38 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 39 |
Correct |
3 ms |
13152 KB |
Output is correct |
| 40 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 41 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 42 |
Correct |
4 ms |
12892 KB |
Output is correct |
| 43 |
Correct |
3 ms |
13008 KB |
Output is correct |
| 44 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 45 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 46 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 47 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 48 |
Correct |
4 ms |
12892 KB |
Output is correct |
| 49 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 50 |
Correct |
3 ms |
12896 KB |
Output is correct |
| 51 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 52 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 53 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 54 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 55 |
Correct |
3 ms |
12912 KB |
Output is correct |
| 56 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 57 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 58 |
Correct |
3 ms |
12892 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
13052 KB |
Output is correct |
| 2 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 3 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 4 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 5 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 6 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 7 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 8 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 9 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 10 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 11 |
Correct |
3 ms |
12956 KB |
Output is correct |
| 12 |
Correct |
3 ms |
12888 KB |
Output is correct |
| 13 |
Correct |
3 ms |
13144 KB |
Output is correct |
| 14 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 15 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 16 |
Correct |
2 ms |
12888 KB |
Output is correct |
| 17 |
Correct |
3 ms |
12948 KB |
Output is correct |
| 18 |
Correct |
3 ms |
12888 KB |
Output is correct |
| 19 |
Correct |
3 ms |
12888 KB |
Output is correct |
| 20 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 21 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 22 |
Correct |
4 ms |
12892 KB |
Output is correct |
| 23 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 24 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 25 |
Correct |
3 ms |
12960 KB |
Output is correct |
| 26 |
Correct |
4 ms |
12892 KB |
Output is correct |
| 27 |
Correct |
4 ms |
12892 KB |
Output is correct |
| 28 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 29 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 30 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 31 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 32 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 33 |
Correct |
2 ms |
13144 KB |
Output is correct |
| 34 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 35 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 36 |
Correct |
2 ms |
12892 KB |
Output is correct |
| 37 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 38 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 39 |
Correct |
3 ms |
13152 KB |
Output is correct |
| 40 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 41 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 42 |
Correct |
4 ms |
12892 KB |
Output is correct |
| 43 |
Correct |
3 ms |
13008 KB |
Output is correct |
| 44 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 45 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 46 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 47 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 48 |
Correct |
4 ms |
12892 KB |
Output is correct |
| 49 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 50 |
Correct |
3 ms |
12896 KB |
Output is correct |
| 51 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 52 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 53 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 54 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 55 |
Correct |
3 ms |
12912 KB |
Output is correct |
| 56 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 57 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 58 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 59 |
Correct |
249 ms |
37860 KB |
Output is correct |
| 60 |
Correct |
287 ms |
40672 KB |
Output is correct |
| 61 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 62 |
Correct |
3 ms |
12892 KB |
Output is correct |
| 63 |
Correct |
219 ms |
35140 KB |
Output is correct |
| 64 |
Correct |
4 ms |
13144 KB |
Output is correct |
| 65 |
Correct |
9 ms |
14428 KB |
Output is correct |
| 66 |
Correct |
56 ms |
25940 KB |
Output is correct |
| 67 |
Correct |
348 ms |
59724 KB |
Output is correct |
| 68 |
Correct |
331 ms |
52700 KB |
Output is correct |
| 69 |
Correct |
7 ms |
13660 KB |
Output is correct |
| 70 |
Correct |
52 ms |
22160 KB |
Output is correct |
| 71 |
Correct |
172 ms |
43936 KB |
Output is correct |
| 72 |
Correct |
210 ms |
42672 KB |
Output is correct |
| 73 |
Correct |
46 ms |
19912 KB |
Output is correct |
| 74 |
Correct |
346 ms |
39688 KB |
Output is correct |
| 75 |
Correct |
16 ms |
16084 KB |
Output is correct |
| 76 |
Correct |
202 ms |
43592 KB |
Output is correct |
| 77 |
Correct |
211 ms |
43756 KB |
Output is correct |
| 78 |
Correct |
17 ms |
16216 KB |
Output is correct |
| 79 |
Correct |
388 ms |
47108 KB |
Output is correct |
| 80 |
Correct |
5 ms |
13144 KB |
Output is correct |
| 81 |
Correct |
73 ms |
22092 KB |
Output is correct |
| 82 |
Correct |
303 ms |
41440 KB |
Output is correct |
| 83 |
Correct |
278 ms |
39612 KB |
Output is correct |
| 84 |
Correct |
284 ms |
39700 KB |
Output is correct |
| 85 |
Correct |
320 ms |
39700 KB |
Output is correct |
| 86 |
Correct |
311 ms |
40712 KB |
Output is correct |
| 87 |
Correct |
302 ms |
40748 KB |
Output is correct |
