Submission #297206

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
297206	2020-09-11T11:08:12 Z	PeppaPig	Network (BOI15_net)	C++14	100 / 100	581 ms	47732 KB

#include <bits/stdc++.h>

using namespace std;

const int N = 5e5 + 5;

int n;
vector<int> g[N], ans;

void dfs(int u, int p) {
	if(g[u].size() == 1) ans.emplace_back(u);
	for(int v : g[u]) if(v != p)
		dfs(v, u);
}

int main() {
	scanf("%d", &n);
	for(int i = 1, a, b; i < n; i++) {
		scanf("%d %d", &a, &b);
		g[a].emplace_back(b);
		g[b].emplace_back(a);
	}
	for(int i = 1; i <= n; i++) if(g[i].size() != 1) {
		dfs(i, 0);
		break;
	}
	
	printf("%d\n", (ans.size() + 1) / 2);
	for(int i = 0; i < ans.size() / 2; i++)
		printf("%d %d\n", ans[i], ans[ans.size() / 2 + i]);
	if(ans.size() & 1)
		printf("%d %d\n", ans[0], ans.back());

	return 0;
}

Compilation message

net.cpp: In function 'int main()':
net.cpp:28:11: warning: format '%d' expects argument of type 'int', but argument 2 has type 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wformat=]
   28 |  printf("%d\n", (ans.size() + 1) / 2);
      |          ~^     ~~~~~~~~~~~~~~~~~~~~
      |           |                      |
      |           int                    std::vector<int>::size_type {aka long unsigned int}
      |          %ld
net.cpp:29:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   29 |  for(int i = 0; i < ans.size() / 2; i++)
      |                 ~~^~~~~~~~~~~~~~~~
net.cpp:17:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   17 |  scanf("%d", &n);
      |  ~~~~~^~~~~~~~~~
net.cpp:19:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   19 |   scanf("%d %d", &a, &b);
      |   ~~~~~^~~~~~~~~~~~~~~~~

Subtask #1
18.0 / 18.0

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

Subtask #2
45.0 / 45.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	8 ms	12032 KB	Output is correct
2	Correct	9 ms	12032 KB	Output is correct
3	Correct	8 ms	12032 KB	Output is correct
4	Correct	9 ms	12032 KB	Output is correct
5	Correct	8 ms	12032 KB	Output is correct
6	Correct	8 ms	12032 KB	Output is correct
7	Correct	8 ms	12032 KB	Output is correct
8	Correct	9 ms	12032 KB	Output is correct
9	Correct	9 ms	12032 KB	Output is correct
10	Correct	10 ms	12032 KB	Output is correct
11	Correct	10 ms	12032 KB	Output is correct
12	Correct	9 ms	12160 KB	Output is correct
13	Correct	9 ms	12032 KB	Output is correct
14	Correct	8 ms	12032 KB	Output is correct
15	Correct	8 ms	12032 KB	Output is correct
16	Correct	9 ms	12032 KB	Output is correct
17	Correct	9 ms	12032 KB	Output is correct
18	Correct	9 ms	12032 KB	Output is correct
19	Correct	9 ms	12032 KB	Output is correct
20	Correct	9 ms	12032 KB	Output is correct
21	Correct	9 ms	12032 KB	Output is correct
22	Correct	10 ms	12160 KB	Output is correct
23	Correct	10 ms	12288 KB	Output is correct
24	Correct	9 ms	12160 KB	Output is correct
25	Correct	9 ms	12160 KB	Output is correct
26	Correct	9 ms	12192 KB	Output is correct
27	Correct	10 ms	12160 KB	Output is correct
28	Correct	10 ms	12160 KB	Output is correct
29	Correct	9 ms	12160 KB	Output is correct
30	Correct	8 ms	12032 KB	Output is correct
31	Correct	10 ms	12160 KB	Output is correct
32	Correct	9 ms	12032 KB	Output is correct
33	Correct	9 ms	12160 KB	Output is correct
34	Correct	8 ms	12032 KB	Output is correct
35	Correct	9 ms	12032 KB	Output is correct
36	Correct	9 ms	12032 KB	Output is correct
37	Correct	9 ms	12032 KB	Output is correct
38	Correct	9 ms	12160 KB	Output is correct
39	Correct	8 ms	12032 KB	Output is correct
40	Correct	9 ms	12032 KB	Output is correct
41	Correct	8 ms	12032 KB	Output is correct
42	Correct	11 ms	12160 KB	Output is correct
43	Correct	9 ms	12160 KB	Output is correct
44	Correct	8 ms	12032 KB	Output is correct
45	Correct	9 ms	12032 KB	Output is correct
46	Correct	9 ms	12032 KB	Output is correct
47	Correct	9 ms	12032 KB	Output is correct
48	Correct	9 ms	12032 KB	Output is correct
49	Correct	9 ms	12160 KB	Output is correct
50	Correct	9 ms	12032 KB	Output is correct
51	Correct	9 ms	12032 KB	Output is correct
52	Correct	9 ms	12032 KB	Output is correct
53	Correct	9 ms	12160 KB	Output is correct
54	Correct	8 ms	12032 KB	Output is correct
55	Correct	9 ms	12032 KB	Output is correct
56	Correct	9 ms	12032 KB	Output is correct
57	Correct	9 ms	12032 KB	Output is correct
58	Correct	10 ms	12160 KB	Output is correct

Subtask #3
37.0 / 37.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	8 ms	12032 KB	Output is correct
2	Correct	9 ms	12032 KB	Output is correct
3	Correct	8 ms	12032 KB	Output is correct
4	Correct	9 ms	12032 KB	Output is correct
5	Correct	8 ms	12032 KB	Output is correct
6	Correct	8 ms	12032 KB	Output is correct
7	Correct	8 ms	12032 KB	Output is correct
8	Correct	9 ms	12032 KB	Output is correct
9	Correct	9 ms	12032 KB	Output is correct
10	Correct	10 ms	12032 KB	Output is correct
11	Correct	10 ms	12032 KB	Output is correct
12	Correct	9 ms	12160 KB	Output is correct
13	Correct	9 ms	12032 KB	Output is correct
14	Correct	8 ms	12032 KB	Output is correct
15	Correct	8 ms	12032 KB	Output is correct
16	Correct	9 ms	12032 KB	Output is correct
17	Correct	9 ms	12032 KB	Output is correct
18	Correct	9 ms	12032 KB	Output is correct
19	Correct	9 ms	12032 KB	Output is correct
20	Correct	9 ms	12032 KB	Output is correct
21	Correct	9 ms	12032 KB	Output is correct
22	Correct	10 ms	12160 KB	Output is correct
23	Correct	10 ms	12288 KB	Output is correct
24	Correct	9 ms	12160 KB	Output is correct
25	Correct	9 ms	12160 KB	Output is correct
26	Correct	9 ms	12192 KB	Output is correct
27	Correct	10 ms	12160 KB	Output is correct
28	Correct	10 ms	12160 KB	Output is correct
29	Correct	9 ms	12160 KB	Output is correct
30	Correct	8 ms	12032 KB	Output is correct
31	Correct	10 ms	12160 KB	Output is correct
32	Correct	9 ms	12032 KB	Output is correct
33	Correct	9 ms	12160 KB	Output is correct
34	Correct	8 ms	12032 KB	Output is correct
35	Correct	9 ms	12032 KB	Output is correct
36	Correct	9 ms	12032 KB	Output is correct
37	Correct	9 ms	12032 KB	Output is correct
38	Correct	9 ms	12160 KB	Output is correct
39	Correct	8 ms	12032 KB	Output is correct
40	Correct	9 ms	12032 KB	Output is correct
41	Correct	8 ms	12032 KB	Output is correct
42	Correct	11 ms	12160 KB	Output is correct
43	Correct	9 ms	12160 KB	Output is correct
44	Correct	8 ms	12032 KB	Output is correct
45	Correct	9 ms	12032 KB	Output is correct
46	Correct	9 ms	12032 KB	Output is correct
47	Correct	9 ms	12032 KB	Output is correct
48	Correct	9 ms	12032 KB	Output is correct
49	Correct	9 ms	12160 KB	Output is correct
50	Correct	9 ms	12032 KB	Output is correct
51	Correct	9 ms	12032 KB	Output is correct
52	Correct	9 ms	12032 KB	Output is correct
53	Correct	9 ms	12160 KB	Output is correct
54	Correct	8 ms	12032 KB	Output is correct
55	Correct	9 ms	12032 KB	Output is correct
56	Correct	9 ms	12032 KB	Output is correct
57	Correct	9 ms	12032 KB	Output is correct
58	Correct	10 ms	12160 KB	Output is correct
59	Correct	451 ms	36196 KB	Output is correct
60	Correct	535 ms	38760 KB	Output is correct
61	Correct	9 ms	12160 KB	Output is correct
62	Correct	9 ms	12032 KB	Output is correct
63	Correct	387 ms	33640 KB	Output is correct
64	Correct	11 ms	12416 KB	Output is correct
65	Correct	22 ms	13952 KB	Output is correct
66	Correct	181 ms	27896 KB	Output is correct
67	Correct	581 ms	46968 KB	Output is correct
68	Correct	575 ms	47732 KB	Output is correct
69	Correct	16 ms	12928 KB	Output is correct
70	Correct	114 ms	21228 KB	Output is correct
71	Correct	368 ms	41824 KB	Output is correct
72	Correct	403 ms	40664 KB	Output is correct
73	Correct	122 ms	19056 KB	Output is correct
74	Correct	532 ms	37748 KB	Output is correct
75	Correct	38 ms	15224 KB	Output is correct
76	Correct	383 ms	41688 KB	Output is correct
77	Correct	382 ms	41820 KB	Output is correct
78	Correct	41 ms	15608 KB	Output is correct
79	Correct	578 ms	45320 KB	Output is correct
80	Correct	11 ms	12288 KB	Output is correct
81	Correct	138 ms	21360 KB	Output is correct
82	Correct	476 ms	39524 KB	Output is correct
83	Correct	535 ms	37796 KB	Output is correct
84	Correct	540 ms	37744 KB	Output is correct
85	Correct	547 ms	37744 KB	Output is correct
86	Correct	528 ms	38756 KB	Output is correct
87	Correct	527 ms	39012 KB	Output is correct

Submission #297206

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