Submission #222606

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
222606	2020-04-13T12:07:59 Z	infinite_iq	Network (BOI15_net)	C++14	18 / 100	17 ms	12168 KB

#define fast ios_base::sync_with_stdio(0),cin.tie(0),cout.tie(0)
#include <bits/stdc++.h>
using namespace std;
#define sqr 340
#define mid (l+r)/2
#define pb push_back
#define ppb pop_back
#define fi first
#define se second
#define lb lower_bound
#define ub upper_bound
#define ins insert
#define era erase
#define C continue
#define mem(dp,i) memset(dp,i,sizeof(dp))
#define mset multiset
typedef long long ll;
typedef short int si;
typedef long double ld;
typedef pair<int,int> pi;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<pi> vpi;
typedef vector<pll> vpll;
const ll inf=1e18;
const ld pai=acos(-1);
int n , root ;
vi v[500009] , leaves;
void dfs( int node , int p ) {
        if ( v[node].size() == 1 ) leaves . pb ( node ) ;
        for ( auto u : v[ node ] ) {
                if ( u == p ) C ;
                dfs ( u , node ) ;
        }
}
int main () {
        cin >> n ;
        for ( int i = 0 ; i < n-1 ; i ++ ) {
                int a , b ;
                cin >> a >> b ;
                a -- , b -- ;
                v[a].pb ( b ) ;
                v[b].pb ( a ) ;
        }
        for ( int i = 0 ; i < n ;i ++ ) {
                if ( v[i].size() != 1 ) {
                        root = i ;
                        break ;
                }
        }
        dfs(root,root);
        vpi ans ;
        int num = leaves.size() ;
        for ( int i = 0 ; i < num ; i ++ ) {
                int j = i + num/2 + (num%2) ;
                if ( j >= num ) break ;
                int a = leaves[i] ;
                int b = leaves[j] ;
                ans.pb ( { a+1 , b+1 } );
        }
          if ( num%2 ) ans.pb ( { leaves[num/2]+1 , 1 } ) ;
        cout << ans.size() << endl ;
        for ( auto u : ans ) cout << u.fi << " " << u.se << endl ;
}

Subtask #1
18.0 / 18.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	12032 KB	Output is correct
2	Correct	12 ms	12032 KB	Output is correct
3	Correct	12 ms	12032 KB	Output is correct
4	Correct	12 ms	12032 KB	Output is correct
5	Correct	11 ms	12032 KB	Output is correct
6	Correct	11 ms	12032 KB	Output is correct
7	Correct	13 ms	12160 KB	Output is correct
8	Correct	12 ms	12032 KB	Output is correct
9	Correct	12 ms	12032 KB	Output is correct
10	Correct	12 ms	12032 KB	Output is correct
11	Correct	15 ms	12032 KB	Output is correct
12	Correct	11 ms	12032 KB	Output is correct
13	Correct	11 ms	12032 KB	Output is correct
14	Correct	12 ms	12032 KB	Output is correct
15	Correct	12 ms	12032 KB	Output is correct
16	Correct	13 ms	12032 KB	Output is correct
17	Correct	13 ms	12032 KB	Output is correct
18	Correct	12 ms	12032 KB	Output is correct
19	Correct	12 ms	12032 KB	Output is correct
20	Correct	12 ms	12032 KB	Output is correct

Subtask #2
0 / 45.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	12032 KB	Output is correct
2	Correct	12 ms	12032 KB	Output is correct
3	Correct	12 ms	12032 KB	Output is correct
4	Correct	12 ms	12032 KB	Output is correct
5	Correct	11 ms	12032 KB	Output is correct
6	Correct	11 ms	12032 KB	Output is correct
7	Correct	13 ms	12160 KB	Output is correct
8	Correct	12 ms	12032 KB	Output is correct
9	Correct	12 ms	12032 KB	Output is correct
10	Correct	12 ms	12032 KB	Output is correct
11	Correct	15 ms	12032 KB	Output is correct
12	Correct	11 ms	12032 KB	Output is correct
13	Correct	11 ms	12032 KB	Output is correct
14	Correct	12 ms	12032 KB	Output is correct
15	Correct	12 ms	12032 KB	Output is correct
16	Correct	13 ms	12032 KB	Output is correct
17	Correct	13 ms	12032 KB	Output is correct
18	Correct	12 ms	12032 KB	Output is correct
19	Correct	12 ms	12032 KB	Output is correct
20	Correct	12 ms	12032 KB	Output is correct
21	Correct	12 ms	12032 KB	Output is correct
22	Correct	17 ms	12168 KB	Output is correct
23	Correct	16 ms	12160 KB	Output is correct
24	Correct	16 ms	12160 KB	Output is correct
25	Correct	14 ms	12160 KB	Output is correct
26	Correct	14 ms	12160 KB	Output is correct
27	Correct	15 ms	12160 KB	Output is correct
28	Correct	15 ms	12160 KB	Output is correct
29	Correct	17 ms	12160 KB	Output is correct
30	Correct	12 ms	12032 KB	Output is correct
31	Correct	15 ms	12160 KB	Output is correct
32	Correct	12 ms	12032 KB	Output is correct
33	Correct	12 ms	12032 KB	Output is correct
34	Correct	12 ms	12032 KB	Output is correct
35	Correct	11 ms	12032 KB	Output is correct
36	Correct	12 ms	12032 KB	Output is correct
37	Correct	12 ms	12032 KB	Output is correct
38	Correct	13 ms	12160 KB	Output is correct
39	Correct	11 ms	12032 KB	Output is correct
40	Correct	12 ms	12032 KB	Output is correct
41	Correct	12 ms	12032 KB	Output is correct
42	Correct	12 ms	12032 KB	Output is correct
43	Correct	14 ms	12160 KB	Output is correct
44	Correct	12 ms	12032 KB	Output is correct
45	Correct	12 ms	12032 KB	Output is correct
46	Correct	13 ms	12032 KB	Output is correct
47	Correct	12 ms	12032 KB	Output is correct
48	Correct	12 ms	12032 KB	Output is correct
49	Correct	14 ms	12160 KB	Output is correct
50	Correct	12 ms	12032 KB	Output is correct
51	Incorrect	12 ms	12032 KB	Breaking single line is causing network to disconnect.
52	Halted	0 ms	0 KB	-

Subtask #3
0 / 37.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	12032 KB	Output is correct
2	Correct	12 ms	12032 KB	Output is correct
3	Correct	12 ms	12032 KB	Output is correct
4	Correct	12 ms	12032 KB	Output is correct
5	Correct	11 ms	12032 KB	Output is correct
6	Correct	11 ms	12032 KB	Output is correct
7	Correct	13 ms	12160 KB	Output is correct
8	Correct	12 ms	12032 KB	Output is correct
9	Correct	12 ms	12032 KB	Output is correct
10	Correct	12 ms	12032 KB	Output is correct
11	Correct	15 ms	12032 KB	Output is correct
12	Correct	11 ms	12032 KB	Output is correct
13	Correct	11 ms	12032 KB	Output is correct
14	Correct	12 ms	12032 KB	Output is correct
15	Correct	12 ms	12032 KB	Output is correct
16	Correct	13 ms	12032 KB	Output is correct
17	Correct	13 ms	12032 KB	Output is correct
18	Correct	12 ms	12032 KB	Output is correct
19	Correct	12 ms	12032 KB	Output is correct
20	Correct	12 ms	12032 KB	Output is correct
21	Correct	12 ms	12032 KB	Output is correct
22	Correct	17 ms	12168 KB	Output is correct
23	Correct	16 ms	12160 KB	Output is correct
24	Correct	16 ms	12160 KB	Output is correct
25	Correct	14 ms	12160 KB	Output is correct
26	Correct	14 ms	12160 KB	Output is correct
27	Correct	15 ms	12160 KB	Output is correct
28	Correct	15 ms	12160 KB	Output is correct
29	Correct	17 ms	12160 KB	Output is correct
30	Correct	12 ms	12032 KB	Output is correct
31	Correct	15 ms	12160 KB	Output is correct
32	Correct	12 ms	12032 KB	Output is correct
33	Correct	12 ms	12032 KB	Output is correct
34	Correct	12 ms	12032 KB	Output is correct
35	Correct	11 ms	12032 KB	Output is correct
36	Correct	12 ms	12032 KB	Output is correct
37	Correct	12 ms	12032 KB	Output is correct
38	Correct	13 ms	12160 KB	Output is correct
39	Correct	11 ms	12032 KB	Output is correct
40	Correct	12 ms	12032 KB	Output is correct
41	Correct	12 ms	12032 KB	Output is correct
42	Correct	12 ms	12032 KB	Output is correct
43	Correct	14 ms	12160 KB	Output is correct
44	Correct	12 ms	12032 KB	Output is correct
45	Correct	12 ms	12032 KB	Output is correct
46	Correct	13 ms	12032 KB	Output is correct
47	Correct	12 ms	12032 KB	Output is correct
48	Correct	12 ms	12032 KB	Output is correct
49	Correct	14 ms	12160 KB	Output is correct
50	Correct	12 ms	12032 KB	Output is correct
51	Incorrect	12 ms	12032 KB	Breaking single line is causing network to disconnect.
52	Halted	0 ms	0 KB	-

Submission #222606

Compilation message

Subtask #1 18.0 / 18.0

Subtask #2 0 / 45.0

Subtask #3 0 / 37.0

Subtask #1
18.0 / 18.0

Subtask #2
0 / 45.0

Subtask #3
0 / 37.0