Submission #91039

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
91039	2018-12-25T20:45:34 Z	sjhuang26	Network (BOI15_net)	C++14	63 / 100	801 ms	76264 KB

#include<iostream>
#include<vector>
using namespace std;
vector<int>s;
vector<int>t[500001];//1 IDX
bool f[500000]={};
int N;
void dfs(int u){
	if(f[u])return;
	f[u]=1;
	if(t[u].size()==1)s.push_back(u);
	for(int&i:t[u])dfs(i);
}
int main(){
	cin>>N;
	for(int i=0;i<N-1;++i){
		int a,b;cin>>a>>b;
		t[a].push_back(b);
		t[b].push_back(a);
	}
	dfs(1);
	int k=s.size();
	if(k%2){
		cout<<k/2+1<<'\n';
		for(int i=0;i<k/2;++i){
			cout<<s[i]<<' '<<s[i+k/2+1]<<'\n';
		}
		cout<<s[k/2]<<' '<<1<<'\n';
	}else{
		cout<<k/2<<'\n';
		for(int i=0;i<k/2;++i){
			cout<<s[i]<<' '<<s[i+k/2]<<'\n';
		}
	}
	return 0;
}

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	12196 KB	Output is correct
3	Correct	12 ms	12240 KB	Output is correct
4	Correct	12 ms	12480 KB	Output is correct
5	Correct	11 ms	12480 KB	Output is correct
6	Correct	12 ms	12480 KB	Output is correct
7	Correct	12 ms	12480 KB	Output is correct
8	Correct	12 ms	12480 KB	Output is correct
9	Correct	11 ms	12480 KB	Output is correct
10	Correct	12 ms	12480 KB	Output is correct
11	Correct	10 ms	12564 KB	Output is correct
12	Correct	10 ms	12564 KB	Output is correct
13	Correct	10 ms	12564 KB	Output is correct
14	Correct	10 ms	12564 KB	Output is correct
15	Correct	11 ms	12564 KB	Output is correct
16	Correct	10 ms	12564 KB	Output is correct
17	Correct	11 ms	12564 KB	Output is correct
18	Correct	10 ms	12564 KB	Output is correct
19	Correct	10 ms	12564 KB	Output is correct
20	Correct	10 ms	12564 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	12196 KB	Output is correct
3	Correct	12 ms	12240 KB	Output is correct
4	Correct	12 ms	12480 KB	Output is correct
5	Correct	11 ms	12480 KB	Output is correct
6	Correct	12 ms	12480 KB	Output is correct
7	Correct	12 ms	12480 KB	Output is correct
8	Correct	12 ms	12480 KB	Output is correct
9	Correct	11 ms	12480 KB	Output is correct
10	Correct	12 ms	12480 KB	Output is correct
11	Correct	10 ms	12564 KB	Output is correct
12	Correct	10 ms	12564 KB	Output is correct
13	Correct	10 ms	12564 KB	Output is correct
14	Correct	10 ms	12564 KB	Output is correct
15	Correct	11 ms	12564 KB	Output is correct
16	Correct	10 ms	12564 KB	Output is correct
17	Correct	11 ms	12564 KB	Output is correct
18	Correct	10 ms	12564 KB	Output is correct
19	Correct	10 ms	12564 KB	Output is correct
20	Correct	10 ms	12564 KB	Output is correct
21	Correct	10 ms	12564 KB	Output is correct
22	Correct	11 ms	12596 KB	Output is correct
23	Correct	12 ms	12636 KB	Output is correct
24	Correct	11 ms	12668 KB	Output is correct
25	Correct	11 ms	12688 KB	Output is correct
26	Correct	11 ms	12720 KB	Output is correct
27	Correct	11 ms	12748 KB	Output is correct
28	Correct	12 ms	12836 KB	Output is correct
29	Correct	12 ms	12836 KB	Output is correct
30	Correct	10 ms	12836 KB	Output is correct
31	Correct	11 ms	12844 KB	Output is correct
32	Correct	10 ms	12844 KB	Output is correct
33	Correct	10 ms	12844 KB	Output is correct
34	Correct	9 ms	12844 KB	Output is correct
35	Correct	12 ms	12844 KB	Output is correct
36	Correct	12 ms	12844 KB	Output is correct
37	Correct	11 ms	12848 KB	Output is correct
38	Correct	11 ms	12856 KB	Output is correct
39	Correct	11 ms	12864 KB	Output is correct
40	Correct	10 ms	12864 KB	Output is correct
41	Correct	10 ms	12864 KB	Output is correct
42	Correct	12 ms	12864 KB	Output is correct
43	Correct	11 ms	12896 KB	Output is correct
44	Correct	10 ms	12896 KB	Output is correct
45	Correct	10 ms	12896 KB	Output is correct
46	Correct	11 ms	12896 KB	Output is correct
47	Correct	10 ms	12896 KB	Output is correct
48	Correct	10 ms	12896 KB	Output is correct
49	Correct	10 ms	12972 KB	Output is correct
50	Correct	10 ms	12972 KB	Output is correct
51	Correct	11 ms	12972 KB	Output is correct
52	Correct	11 ms	12972 KB	Output is correct
53	Correct	10 ms	13064 KB	Output is correct
54	Correct	12 ms	13064 KB	Output is correct
55	Correct	11 ms	13064 KB	Output is correct
56	Correct	12 ms	13064 KB	Output is correct
57	Correct	12 ms	13064 KB	Output is correct
58	Correct	13 ms	13064 KB	Output is correct

Subtask #3
0 / 37.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	12024 KB	Output is correct
2	Correct	12 ms	12196 KB	Output is correct
3	Correct	12 ms	12240 KB	Output is correct
4	Correct	12 ms	12480 KB	Output is correct
5	Correct	11 ms	12480 KB	Output is correct
6	Correct	12 ms	12480 KB	Output is correct
7	Correct	12 ms	12480 KB	Output is correct
8	Correct	12 ms	12480 KB	Output is correct
9	Correct	11 ms	12480 KB	Output is correct
10	Correct	12 ms	12480 KB	Output is correct
11	Correct	10 ms	12564 KB	Output is correct
12	Correct	10 ms	12564 KB	Output is correct
13	Correct	10 ms	12564 KB	Output is correct
14	Correct	10 ms	12564 KB	Output is correct
15	Correct	11 ms	12564 KB	Output is correct
16	Correct	10 ms	12564 KB	Output is correct
17	Correct	11 ms	12564 KB	Output is correct
18	Correct	10 ms	12564 KB	Output is correct
19	Correct	10 ms	12564 KB	Output is correct
20	Correct	10 ms	12564 KB	Output is correct
21	Correct	10 ms	12564 KB	Output is correct
22	Correct	11 ms	12596 KB	Output is correct
23	Correct	12 ms	12636 KB	Output is correct
24	Correct	11 ms	12668 KB	Output is correct
25	Correct	11 ms	12688 KB	Output is correct
26	Correct	11 ms	12720 KB	Output is correct
27	Correct	11 ms	12748 KB	Output is correct
28	Correct	12 ms	12836 KB	Output is correct
29	Correct	12 ms	12836 KB	Output is correct
30	Correct	10 ms	12836 KB	Output is correct
31	Correct	11 ms	12844 KB	Output is correct
32	Correct	10 ms	12844 KB	Output is correct
33	Correct	10 ms	12844 KB	Output is correct
34	Correct	9 ms	12844 KB	Output is correct
35	Correct	12 ms	12844 KB	Output is correct
36	Correct	12 ms	12844 KB	Output is correct
37	Correct	11 ms	12848 KB	Output is correct
38	Correct	11 ms	12856 KB	Output is correct
39	Correct	11 ms	12864 KB	Output is correct
40	Correct	10 ms	12864 KB	Output is correct
41	Correct	10 ms	12864 KB	Output is correct
42	Correct	12 ms	12864 KB	Output is correct
43	Correct	11 ms	12896 KB	Output is correct
44	Correct	10 ms	12896 KB	Output is correct
45	Correct	10 ms	12896 KB	Output is correct
46	Correct	11 ms	12896 KB	Output is correct
47	Correct	10 ms	12896 KB	Output is correct
48	Correct	10 ms	12896 KB	Output is correct
49	Correct	10 ms	12972 KB	Output is correct
50	Correct	10 ms	12972 KB	Output is correct
51	Correct	11 ms	12972 KB	Output is correct
52	Correct	11 ms	12972 KB	Output is correct
53	Correct	10 ms	13064 KB	Output is correct
54	Correct	12 ms	13064 KB	Output is correct
55	Correct	11 ms	13064 KB	Output is correct
56	Correct	12 ms	13064 KB	Output is correct
57	Correct	12 ms	13064 KB	Output is correct
58	Correct	13 ms	13064 KB	Output is correct
59	Correct	648 ms	37412 KB	Output is correct
60	Runtime error	801 ms	76264 KB	Execution killed with signal 11 (could be triggered by violating memory limits)
61	Halted	0 ms	0 KB	-

Submission #91039

Compilation message

Subtask #1 18.0 / 18.0

Subtask #2 45.0 / 45.0

Subtask #3 0 / 37.0

Subtask #1
18.0 / 18.0

Subtask #2
45.0 / 45.0

Subtask #3
0 / 37.0