Submission #75937

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
75937	2018-09-11T15:48:23 Z	Vasiljko	Network (BOI15_net)	C++14	100 / 100	622 ms	152764 KB

#include <bits/stdc++.h>
using namespace std;

const int N = 5e5+10;
vector<int>leaf;
vector<int>v[N];
void dfs(int s,int p){
	if(v[s].size()==1){
		leaf.push_back(s);
	}
	for(int i=0;i<v[s].size();i++){
		if(v[s][i]!=p){
			dfs(v[s][i],s);
		}
	}
}

int main() {
	ios_base::sync_with_stdio(false);cin.tie(nullptr);cout.tie(nullptr);

	int n,x,y;
	cin>>n;
	for(int i=0;i<n-1;i++){
		cin>>x>>y;
		v[x].push_back(y);
		v[y].push_back(x);
	}

	dfs(1,-1);
	int k=(int)leaf.size();
	if(k%2==0){
		cout<<k/2<<"\n";
		for(int i=0;i<k/2;i++){
			cout<<leaf[i]<<" "<<leaf[i+k/2]<<"\n";
		}
	}else{
		cout<<k/2+1<<"\n";
		for(int i=0;i<k/2;i++){
			cout<<leaf[i]<<" "<<leaf[i+k/2+1]<<"\n";
		}
		cout<<leaf[k/2]<<" "<<1;
	}

	return 0;
}

Compilation message

net.cpp: In function 'void dfs(int, int)':
net.cpp:11:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<v[s].size();i++){
              ~^~~~~~~~~~~~

Subtask #1
18.0 / 18.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	12024 KB	Output is correct
2	Correct	12 ms	12024 KB	Output is correct
3	Correct	12 ms	12040 KB	Output is correct
4	Correct	12 ms	12196 KB	Output is correct
5	Correct	12 ms	12196 KB	Output is correct
6	Correct	12 ms	12200 KB	Output is correct
7	Correct	12 ms	12244 KB	Output is correct
8	Correct	13 ms	12320 KB	Output is correct
9	Correct	12 ms	12320 KB	Output is correct
10	Correct	13 ms	12320 KB	Output is correct
11	Correct	12 ms	12320 KB	Output is correct
12	Correct	12 ms	12320 KB	Output is correct
13	Correct	13 ms	12368 KB	Output is correct
14	Correct	15 ms	12368 KB	Output is correct
15	Correct	12 ms	12368 KB	Output is correct
16	Correct	13 ms	12368 KB	Output is correct
17	Correct	14 ms	12368 KB	Output is correct
18	Correct	12 ms	12368 KB	Output is correct
19	Correct	12 ms	12368 KB	Output is correct
20	Correct	12 ms	12368 KB	Output is correct

Subtask #2
45.0 / 45.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	12024 KB	Output is correct
2	Correct	12 ms	12024 KB	Output is correct
3	Correct	12 ms	12040 KB	Output is correct
4	Correct	12 ms	12196 KB	Output is correct
5	Correct	12 ms	12196 KB	Output is correct
6	Correct	12 ms	12200 KB	Output is correct
7	Correct	12 ms	12244 KB	Output is correct
8	Correct	13 ms	12320 KB	Output is correct
9	Correct	12 ms	12320 KB	Output is correct
10	Correct	13 ms	12320 KB	Output is correct
11	Correct	12 ms	12320 KB	Output is correct
12	Correct	12 ms	12320 KB	Output is correct
13	Correct	13 ms	12368 KB	Output is correct
14	Correct	15 ms	12368 KB	Output is correct
15	Correct	12 ms	12368 KB	Output is correct
16	Correct	13 ms	12368 KB	Output is correct
17	Correct	14 ms	12368 KB	Output is correct
18	Correct	12 ms	12368 KB	Output is correct
19	Correct	12 ms	12368 KB	Output is correct
20	Correct	12 ms	12368 KB	Output is correct
21	Correct	12 ms	12368 KB	Output is correct
22	Correct	13 ms	12396 KB	Output is correct
23	Correct	13 ms	12396 KB	Output is correct
24	Correct	17 ms	12412 KB	Output is correct
25	Correct	13 ms	12428 KB	Output is correct
26	Correct	13 ms	12428 KB	Output is correct
27	Correct	14 ms	12432 KB	Output is correct
28	Correct	17 ms	12444 KB	Output is correct
29	Correct	13 ms	12460 KB	Output is correct
30	Correct	12 ms	12460 KB	Output is correct
31	Correct	13 ms	12476 KB	Output is correct
32	Correct	18 ms	12476 KB	Output is correct
33	Correct	13 ms	12476 KB	Output is correct
34	Correct	15 ms	12476 KB	Output is correct
35	Correct	13 ms	12476 KB	Output is correct
36	Correct	13 ms	12476 KB	Output is correct
37	Correct	13 ms	12476 KB	Output is correct
38	Correct	19 ms	12596 KB	Output is correct
39	Correct	12 ms	12596 KB	Output is correct
40	Correct	18 ms	12596 KB	Output is correct
41	Correct	13 ms	12596 KB	Output is correct
42	Correct	12 ms	12596 KB	Output is correct
43	Correct	15 ms	12596 KB	Output is correct
44	Correct	17 ms	12596 KB	Output is correct
45	Correct	14 ms	12596 KB	Output is correct
46	Correct	13 ms	12596 KB	Output is correct
47	Correct	13 ms	12596 KB	Output is correct
48	Correct	12 ms	12596 KB	Output is correct
49	Correct	13 ms	12596 KB	Output is correct
50	Correct	12 ms	12596 KB	Output is correct
51	Correct	12 ms	12596 KB	Output is correct
52	Correct	12 ms	12596 KB	Output is correct
53	Correct	13 ms	12596 KB	Output is correct
54	Correct	12 ms	12596 KB	Output is correct
55	Correct	13 ms	12596 KB	Output is correct
56	Correct	13 ms	12596 KB	Output is correct
57	Correct	14 ms	12596 KB	Output is correct
58	Correct	13 ms	12596 KB	Output is correct

Subtask #3
37.0 / 37.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	12024 KB	Output is correct
2	Correct	12 ms	12024 KB	Output is correct
3	Correct	12 ms	12040 KB	Output is correct
4	Correct	12 ms	12196 KB	Output is correct
5	Correct	12 ms	12196 KB	Output is correct
6	Correct	12 ms	12200 KB	Output is correct
7	Correct	12 ms	12244 KB	Output is correct
8	Correct	13 ms	12320 KB	Output is correct
9	Correct	12 ms	12320 KB	Output is correct
10	Correct	13 ms	12320 KB	Output is correct
11	Correct	12 ms	12320 KB	Output is correct
12	Correct	12 ms	12320 KB	Output is correct
13	Correct	13 ms	12368 KB	Output is correct
14	Correct	15 ms	12368 KB	Output is correct
15	Correct	12 ms	12368 KB	Output is correct
16	Correct	13 ms	12368 KB	Output is correct
17	Correct	14 ms	12368 KB	Output is correct
18	Correct	12 ms	12368 KB	Output is correct
19	Correct	12 ms	12368 KB	Output is correct
20	Correct	12 ms	12368 KB	Output is correct
21	Correct	12 ms	12368 KB	Output is correct
22	Correct	13 ms	12396 KB	Output is correct
23	Correct	13 ms	12396 KB	Output is correct
24	Correct	17 ms	12412 KB	Output is correct
25	Correct	13 ms	12428 KB	Output is correct
26	Correct	13 ms	12428 KB	Output is correct
27	Correct	14 ms	12432 KB	Output is correct
28	Correct	17 ms	12444 KB	Output is correct
29	Correct	13 ms	12460 KB	Output is correct
30	Correct	12 ms	12460 KB	Output is correct
31	Correct	13 ms	12476 KB	Output is correct
32	Correct	18 ms	12476 KB	Output is correct
33	Correct	13 ms	12476 KB	Output is correct
34	Correct	15 ms	12476 KB	Output is correct
35	Correct	13 ms	12476 KB	Output is correct
36	Correct	13 ms	12476 KB	Output is correct
37	Correct	13 ms	12476 KB	Output is correct
38	Correct	19 ms	12596 KB	Output is correct
39	Correct	12 ms	12596 KB	Output is correct
40	Correct	18 ms	12596 KB	Output is correct
41	Correct	13 ms	12596 KB	Output is correct
42	Correct	12 ms	12596 KB	Output is correct
43	Correct	15 ms	12596 KB	Output is correct
44	Correct	17 ms	12596 KB	Output is correct
45	Correct	14 ms	12596 KB	Output is correct
46	Correct	13 ms	12596 KB	Output is correct
47	Correct	13 ms	12596 KB	Output is correct
48	Correct	12 ms	12596 KB	Output is correct
49	Correct	13 ms	12596 KB	Output is correct
50	Correct	12 ms	12596 KB	Output is correct
51	Correct	12 ms	12596 KB	Output is correct
52	Correct	12 ms	12596 KB	Output is correct
53	Correct	13 ms	12596 KB	Output is correct
54	Correct	12 ms	12596 KB	Output is correct
55	Correct	13 ms	12596 KB	Output is correct
56	Correct	13 ms	12596 KB	Output is correct
57	Correct	14 ms	12596 KB	Output is correct
58	Correct	13 ms	12596 KB	Output is correct
59	Correct	444 ms	36396 KB	Output is correct
60	Correct	562 ms	45200 KB	Output is correct
61	Correct	14 ms	45200 KB	Output is correct
62	Correct	13 ms	45200 KB	Output is correct
63	Correct	380 ms	46516 KB	Output is correct
64	Correct	19 ms	46516 KB	Output is correct
65	Correct	26 ms	46516 KB	Output is correct
66	Correct	170 ms	46516 KB	Output is correct
67	Correct	602 ms	67760 KB	Output is correct
68	Correct	591 ms	75280 KB	Output is correct
69	Correct	25 ms	75280 KB	Output is correct
70	Correct	126 ms	75280 KB	Output is correct
71	Correct	335 ms	78284 KB	Output is correct
72	Correct	379 ms	83780 KB	Output is correct
73	Correct	113 ms	83780 KB	Output is correct
74	Correct	529 ms	89040 KB	Output is correct
75	Correct	43 ms	89040 KB	Output is correct
76	Correct	397 ms	100048 KB	Output is correct
77	Correct	360 ms	106672 KB	Output is correct
78	Correct	45 ms	106672 KB	Output is correct
79	Correct	622 ms	117512 KB	Output is correct
80	Correct	14 ms	117512 KB	Output is correct
81	Correct	128 ms	117512 KB	Output is correct
82	Correct	445 ms	120484 KB	Output is correct
83	Correct	509 ms	125200 KB	Output is correct
84	Correct	505 ms	131968 KB	Output is correct
85	Correct	498 ms	138472 KB	Output is correct
86	Correct	495 ms	146128 KB	Output is correct
87	Correct	521 ms	152764 KB	Output is correct

Submission #75937

Compilation message

Subtask #1 18.0 / 18.0

Subtask #2 45.0 / 45.0

Subtask #3 37.0 / 37.0

Subtask #1
18.0 / 18.0

Subtask #2
45.0 / 45.0

Subtask #3
37.0 / 37.0