Submission #134621

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
134621	2019-07-23T05:43:36 Z	Ace	Network (BOI15_net)	C++14	100 / 100	634 ms	47916 KB

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

const int N = 5e5;

int n;
vector<int> adj[N+5];
vector<int> leaf;

void dfs(int x, int par){
	if(adj[x].size() == 1){
		leaf.push_back(x);
		return;
	}
	for(int i=0;i<adj[x].size();i++){
		if(adj[x][i] == par) continue;
		dfs(adj[x][i],x);
	}
	return;
}

int main(){
	scanf("%d",&n);
	for(int i=1;i<n;i++){
		int u,v;
		scanf("%d%d",&u,&v);
		adj[u].push_back(v);
		adj[v].push_back(u);
	}
	int cnt = 0;
	for(int i=1;i<=n;i++){
		if(adj[i].size()!=1){
			dfs(i,-1);
			break;
		}
	}
	if(leaf.size()&1){
		leaf.push_back(leaf[0]);
	}
	printf("%d\n",leaf.size()/2);
	for(int i=0;i<leaf.size()/2;i++){
		printf("%d %d\n",leaf[i],leaf[i+leaf.size()/2]);
	}
	return 0;
}

Compilation message

net.cpp: In function 'void dfs(int, int)':
net.cpp:15:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<adj[x].size();i++){
              ~^~~~~~~~~~~~~~
net.cpp: In function 'int main()':
net.cpp:40:29: warning: format '%d' expects argument of type 'int', but argument 2 has type 'std::vector<int>::size_type {aka long unsigned int}' [-Wformat=]
  printf("%d\n",leaf.size()/2);
                ~~~~~~~~~~~~~^
net.cpp:41:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<leaf.size()/2;i++){
              ~^~~~~~~~~~~~~~
net.cpp:30:6: warning: unused variable 'cnt' [-Wunused-variable]
  int cnt = 0;
      ^~~
net.cpp:23:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ~~~~~^~~~~~~~~
net.cpp:26:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d",&u,&v);
   ~~~~~^~~~~~~~~~~~~~

Subtask #1
18.0 / 18.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	12024 KB	Output is correct
2	Correct	13 ms	12024 KB	Output is correct
3	Correct	13 ms	12024 KB	Output is correct
4	Correct	15 ms	12024 KB	Output is correct
5	Correct	15 ms	12024 KB	Output is correct
6	Correct	15 ms	12024 KB	Output is correct
7	Correct	13 ms	12024 KB	Output is correct
8	Correct	20 ms	12024 KB	Output is correct
9	Correct	13 ms	12024 KB	Output is correct
10	Correct	12 ms	12024 KB	Output is correct
11	Correct	13 ms	12024 KB	Output is correct
12	Correct	13 ms	12024 KB	Output is correct
13	Correct	13 ms	12024 KB	Output is correct
14	Correct	13 ms	12024 KB	Output is correct
15	Correct	12 ms	12024 KB	Output is correct
16	Correct	12 ms	12024 KB	Output is correct
17	Correct	13 ms	12024 KB	Output is correct
18	Correct	13 ms	12024 KB	Output is correct
19	Correct	13 ms	12024 KB	Output is correct
20	Correct	12 ms	12052 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	13 ms	12024 KB	Output is correct
3	Correct	13 ms	12024 KB	Output is correct
4	Correct	15 ms	12024 KB	Output is correct
5	Correct	15 ms	12024 KB	Output is correct
6	Correct	15 ms	12024 KB	Output is correct
7	Correct	13 ms	12024 KB	Output is correct
8	Correct	20 ms	12024 KB	Output is correct
9	Correct	13 ms	12024 KB	Output is correct
10	Correct	12 ms	12024 KB	Output is correct
11	Correct	13 ms	12024 KB	Output is correct
12	Correct	13 ms	12024 KB	Output is correct
13	Correct	13 ms	12024 KB	Output is correct
14	Correct	13 ms	12024 KB	Output is correct
15	Correct	12 ms	12024 KB	Output is correct
16	Correct	12 ms	12024 KB	Output is correct
17	Correct	13 ms	12024 KB	Output is correct
18	Correct	13 ms	12024 KB	Output is correct
19	Correct	13 ms	12024 KB	Output is correct
20	Correct	12 ms	12052 KB	Output is correct
21	Correct	17 ms	12024 KB	Output is correct
22	Correct	14 ms	12152 KB	Output is correct
23	Correct	14 ms	12152 KB	Output is correct
24	Correct	13 ms	12152 KB	Output is correct
25	Correct	14 ms	12280 KB	Output is correct
26	Correct	13 ms	12152 KB	Output is correct
27	Correct	16 ms	12152 KB	Output is correct
28	Correct	16 ms	12152 KB	Output is correct
29	Correct	14 ms	12152 KB	Output is correct
30	Correct	13 ms	12024 KB	Output is correct
31	Correct	13 ms	12152 KB	Output is correct
32	Correct	15 ms	12028 KB	Output is correct
33	Correct	16 ms	12152 KB	Output is correct
34	Correct	13 ms	12024 KB	Output is correct
35	Correct	15 ms	12024 KB	Output is correct
36	Correct	13 ms	12024 KB	Output is correct
37	Correct	16 ms	12152 KB	Output is correct
38	Correct	16 ms	12152 KB	Output is correct
39	Correct	13 ms	12024 KB	Output is correct
40	Correct	13 ms	12024 KB	Output is correct
41	Correct	13 ms	12024 KB	Output is correct
42	Correct	13 ms	12152 KB	Output is correct
43	Correct	13 ms	12028 KB	Output is correct
44	Correct	16 ms	12024 KB	Output is correct
45	Correct	16 ms	12024 KB	Output is correct
46	Correct	13 ms	12024 KB	Output is correct
47	Correct	16 ms	12024 KB	Output is correct
48	Correct	12 ms	12024 KB	Output is correct
49	Correct	13 ms	12152 KB	Output is correct
50	Correct	13 ms	12024 KB	Output is correct
51	Correct	13 ms	12152 KB	Output is correct
52	Correct	13 ms	12024 KB	Output is correct
53	Correct	13 ms	12152 KB	Output is correct
54	Correct	13 ms	12024 KB	Output is correct
55	Correct	13 ms	12152 KB	Output is correct
56	Correct	13 ms	12024 KB	Output is correct
57	Correct	13 ms	12152 KB	Output is correct
58	Correct	14 ms	12124 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	13 ms	12024 KB	Output is correct
3	Correct	13 ms	12024 KB	Output is correct
4	Correct	15 ms	12024 KB	Output is correct
5	Correct	15 ms	12024 KB	Output is correct
6	Correct	15 ms	12024 KB	Output is correct
7	Correct	13 ms	12024 KB	Output is correct
8	Correct	20 ms	12024 KB	Output is correct
9	Correct	13 ms	12024 KB	Output is correct
10	Correct	12 ms	12024 KB	Output is correct
11	Correct	13 ms	12024 KB	Output is correct
12	Correct	13 ms	12024 KB	Output is correct
13	Correct	13 ms	12024 KB	Output is correct
14	Correct	13 ms	12024 KB	Output is correct
15	Correct	12 ms	12024 KB	Output is correct
16	Correct	12 ms	12024 KB	Output is correct
17	Correct	13 ms	12024 KB	Output is correct
18	Correct	13 ms	12024 KB	Output is correct
19	Correct	13 ms	12024 KB	Output is correct
20	Correct	12 ms	12052 KB	Output is correct
21	Correct	17 ms	12024 KB	Output is correct
22	Correct	14 ms	12152 KB	Output is correct
23	Correct	14 ms	12152 KB	Output is correct
24	Correct	13 ms	12152 KB	Output is correct
25	Correct	14 ms	12280 KB	Output is correct
26	Correct	13 ms	12152 KB	Output is correct
27	Correct	16 ms	12152 KB	Output is correct
28	Correct	16 ms	12152 KB	Output is correct
29	Correct	14 ms	12152 KB	Output is correct
30	Correct	13 ms	12024 KB	Output is correct
31	Correct	13 ms	12152 KB	Output is correct
32	Correct	15 ms	12028 KB	Output is correct
33	Correct	16 ms	12152 KB	Output is correct
34	Correct	13 ms	12024 KB	Output is correct
35	Correct	15 ms	12024 KB	Output is correct
36	Correct	13 ms	12024 KB	Output is correct
37	Correct	16 ms	12152 KB	Output is correct
38	Correct	16 ms	12152 KB	Output is correct
39	Correct	13 ms	12024 KB	Output is correct
40	Correct	13 ms	12024 KB	Output is correct
41	Correct	13 ms	12024 KB	Output is correct
42	Correct	13 ms	12152 KB	Output is correct
43	Correct	13 ms	12028 KB	Output is correct
44	Correct	16 ms	12024 KB	Output is correct
45	Correct	16 ms	12024 KB	Output is correct
46	Correct	13 ms	12024 KB	Output is correct
47	Correct	16 ms	12024 KB	Output is correct
48	Correct	12 ms	12024 KB	Output is correct
49	Correct	13 ms	12152 KB	Output is correct
50	Correct	13 ms	12024 KB	Output is correct
51	Correct	13 ms	12152 KB	Output is correct
52	Correct	13 ms	12024 KB	Output is correct
53	Correct	13 ms	12152 KB	Output is correct
54	Correct	13 ms	12024 KB	Output is correct
55	Correct	13 ms	12152 KB	Output is correct
56	Correct	13 ms	12024 KB	Output is correct
57	Correct	13 ms	12152 KB	Output is correct
58	Correct	14 ms	12124 KB	Output is correct
59	Correct	479 ms	36080 KB	Output is correct
60	Correct	622 ms	38888 KB	Output is correct
61	Correct	12 ms	12024 KB	Output is correct
62	Correct	15 ms	12024 KB	Output is correct
63	Correct	356 ms	33748 KB	Output is correct
64	Correct	16 ms	12536 KB	Output is correct
65	Correct	27 ms	13944 KB	Output is correct
66	Correct	169 ms	27896 KB	Output is correct
67	Correct	602 ms	47100 KB	Output is correct
68	Correct	634 ms	47916 KB	Output is correct
69	Correct	20 ms	12920 KB	Output is correct
70	Correct	153 ms	21232 KB	Output is correct
71	Correct	368 ms	41888 KB	Output is correct
72	Correct	360 ms	40812 KB	Output is correct
73	Correct	118 ms	19056 KB	Output is correct
74	Correct	516 ms	37764 KB	Output is correct
75	Correct	42 ms	15224 KB	Output is correct
76	Correct	355 ms	41680 KB	Output is correct
77	Correct	352 ms	41680 KB	Output is correct
78	Correct	56 ms	15580 KB	Output is correct
79	Correct	581 ms	45428 KB	Output is correct
80	Correct	15 ms	12284 KB	Output is correct
81	Correct	131 ms	21236 KB	Output is correct
82	Correct	440 ms	39656 KB	Output is correct
83	Correct	517 ms	37884 KB	Output is correct
84	Correct	515 ms	37652 KB	Output is correct
85	Correct	511 ms	37828 KB	Output is correct
86	Correct	484 ms	38748 KB	Output is correct
87	Correct	492 ms	38872 KB	Output is correct

Submission #134621

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