Submission #705324

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
705324	2023-03-04T01:07:59 Z	anha3k25cvp	Network (BOI15_net)	C++14	100 / 100	411 ms	49836 KB

#include <bits/stdc++.h>
#define ll long long
#define dl double
#define st first
#define nd second
#define II pair <int, int>

using namespace std;

const int N = 1 + 1e5;
const int inf = 7 + 1e9;

vector <int> h, q;
vector <vector <int>> g;

void dfs(int u) {
    if (g[u].size() == 1)
        q.push_back(u);
    for (int v : g[u])
        if (!h[v]) {
            h[v] = h[u] + 1;
            dfs(v);
        }
}

int main() {
#define TASKNAME "net"
    ios_base :: sync_with_stdio (0);
    cin.tie (0);
    if ( fopen( TASKNAME".inp", "r" ) ) {
        freopen( TASKNAME".inp", "r", stdin );
        freopen( TASKNAME".out", "w", stdout );
    }
    int n;
    cin >> n;
    g.resize(n + 1);
    for (int i = 1; i < n; i ++) {
        int u, v;
        cin >> u >> v;
        g[u].push_back(v);
        g[v].push_back(u);
    }
    h.assign(n + 1, 0);
    h[1] = 1;
    dfs(1);
    int m = q.size();
    vector <II> ans;
    for (int i = 0; i < m / 2; i ++)
        ans.push_back({q[i], q[(m / 2) + i]});
    if (m & 1)
        ans.push_back({q[0], q.back()});
    cout << ans.size() << '\n';
    for (auto z : ans)
        cout << z.st << ' ' << z.nd << '\n';
    return 0;
}

Compilation message

net.cpp: In function 'int main()':
net.cpp:31:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   31 |         freopen( TASKNAME".inp", "r", stdin );
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
net.cpp:32:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   32 |         freopen( TASKNAME".out", "w", stdout );
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
18.0 / 18.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	212 KB	Output is correct
2	Correct	0 ms	212 KB	Output is correct
3	Correct	0 ms	224 KB	Output is correct
4	Correct	0 ms	316 KB	Output is correct
5	Correct	1 ms	316 KB	Output is correct
6	Correct	0 ms	212 KB	Output is correct
7	Correct	0 ms	324 KB	Output is correct
8	Correct	0 ms	212 KB	Output is correct
9	Correct	0 ms	324 KB	Output is correct
10	Correct	0 ms	212 KB	Output is correct
11	Correct	0 ms	212 KB	Output is correct
12	Correct	0 ms	212 KB	Output is correct
13	Correct	0 ms	212 KB	Output is correct
14	Correct	0 ms	212 KB	Output is correct
15	Correct	1 ms	212 KB	Output is correct
16	Correct	0 ms	212 KB	Output is correct
17	Correct	0 ms	212 KB	Output is correct
18	Correct	0 ms	320 KB	Output is correct
19	Correct	1 ms	212 KB	Output is correct
20	Correct	1 ms	212 KB	Output is correct

Subtask #2
45.0 / 45.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	212 KB	Output is correct
2	Correct	0 ms	212 KB	Output is correct
3	Correct	0 ms	224 KB	Output is correct
4	Correct	0 ms	316 KB	Output is correct
5	Correct	1 ms	316 KB	Output is correct
6	Correct	0 ms	212 KB	Output is correct
7	Correct	0 ms	324 KB	Output is correct
8	Correct	0 ms	212 KB	Output is correct
9	Correct	0 ms	324 KB	Output is correct
10	Correct	0 ms	212 KB	Output is correct
11	Correct	0 ms	212 KB	Output is correct
12	Correct	0 ms	212 KB	Output is correct
13	Correct	0 ms	212 KB	Output is correct
14	Correct	0 ms	212 KB	Output is correct
15	Correct	1 ms	212 KB	Output is correct
16	Correct	0 ms	212 KB	Output is correct
17	Correct	0 ms	212 KB	Output is correct
18	Correct	0 ms	320 KB	Output is correct
19	Correct	1 ms	212 KB	Output is correct
20	Correct	1 ms	212 KB	Output is correct
21	Correct	0 ms	212 KB	Output is correct
22	Correct	1 ms	468 KB	Output is correct
23	Correct	1 ms	468 KB	Output is correct
24	Correct	1 ms	468 KB	Output is correct
25	Correct	1 ms	468 KB	Output is correct
26	Correct	1 ms	340 KB	Output is correct
27	Correct	1 ms	432 KB	Output is correct
28	Correct	1 ms	468 KB	Output is correct
29	Correct	1 ms	340 KB	Output is correct
30	Correct	0 ms	212 KB	Output is correct
31	Correct	1 ms	468 KB	Output is correct
32	Correct	0 ms	212 KB	Output is correct
33	Correct	1 ms	212 KB	Output is correct
34	Correct	0 ms	320 KB	Output is correct
35	Correct	0 ms	212 KB	Output is correct
36	Correct	0 ms	212 KB	Output is correct
37	Correct	1 ms	324 KB	Output is correct
38	Correct	1 ms	340 KB	Output is correct
39	Correct	0 ms	320 KB	Output is correct
40	Correct	0 ms	316 KB	Output is correct
41	Correct	0 ms	320 KB	Output is correct
42	Correct	1 ms	340 KB	Output is correct
43	Correct	1 ms	340 KB	Output is correct
44	Correct	0 ms	212 KB	Output is correct
45	Correct	1 ms	340 KB	Output is correct
46	Correct	1 ms	340 KB	Output is correct
47	Correct	0 ms	212 KB	Output is correct
48	Correct	0 ms	340 KB	Output is correct
49	Correct	1 ms	340 KB	Output is correct
50	Correct	0 ms	212 KB	Output is correct
51	Correct	1 ms	212 KB	Output is correct
52	Correct	0 ms	324 KB	Output is correct
53	Correct	1 ms	340 KB	Output is correct
54	Correct	1 ms	324 KB	Output is correct
55	Correct	1 ms	340 KB	Output is correct
56	Correct	1 ms	212 KB	Output is correct
57	Correct	1 ms	324 KB	Output is correct
58	Correct	1 ms	468 KB	Output is correct

Subtask #3
37.0 / 37.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	212 KB	Output is correct
2	Correct	0 ms	212 KB	Output is correct
3	Correct	0 ms	224 KB	Output is correct
4	Correct	0 ms	316 KB	Output is correct
5	Correct	1 ms	316 KB	Output is correct
6	Correct	0 ms	212 KB	Output is correct
7	Correct	0 ms	324 KB	Output is correct
8	Correct	0 ms	212 KB	Output is correct
9	Correct	0 ms	324 KB	Output is correct
10	Correct	0 ms	212 KB	Output is correct
11	Correct	0 ms	212 KB	Output is correct
12	Correct	0 ms	212 KB	Output is correct
13	Correct	0 ms	212 KB	Output is correct
14	Correct	0 ms	212 KB	Output is correct
15	Correct	1 ms	212 KB	Output is correct
16	Correct	0 ms	212 KB	Output is correct
17	Correct	0 ms	212 KB	Output is correct
18	Correct	0 ms	320 KB	Output is correct
19	Correct	1 ms	212 KB	Output is correct
20	Correct	1 ms	212 KB	Output is correct
21	Correct	0 ms	212 KB	Output is correct
22	Correct	1 ms	468 KB	Output is correct
23	Correct	1 ms	468 KB	Output is correct
24	Correct	1 ms	468 KB	Output is correct
25	Correct	1 ms	468 KB	Output is correct
26	Correct	1 ms	340 KB	Output is correct
27	Correct	1 ms	432 KB	Output is correct
28	Correct	1 ms	468 KB	Output is correct
29	Correct	1 ms	340 KB	Output is correct
30	Correct	0 ms	212 KB	Output is correct
31	Correct	1 ms	468 KB	Output is correct
32	Correct	0 ms	212 KB	Output is correct
33	Correct	1 ms	212 KB	Output is correct
34	Correct	0 ms	320 KB	Output is correct
35	Correct	0 ms	212 KB	Output is correct
36	Correct	0 ms	212 KB	Output is correct
37	Correct	1 ms	324 KB	Output is correct
38	Correct	1 ms	340 KB	Output is correct
39	Correct	0 ms	320 KB	Output is correct
40	Correct	0 ms	316 KB	Output is correct
41	Correct	0 ms	320 KB	Output is correct
42	Correct	1 ms	340 KB	Output is correct
43	Correct	1 ms	340 KB	Output is correct
44	Correct	0 ms	212 KB	Output is correct
45	Correct	1 ms	340 KB	Output is correct
46	Correct	1 ms	340 KB	Output is correct
47	Correct	0 ms	212 KB	Output is correct
48	Correct	0 ms	340 KB	Output is correct
49	Correct	1 ms	340 KB	Output is correct
50	Correct	0 ms	212 KB	Output is correct
51	Correct	1 ms	212 KB	Output is correct
52	Correct	0 ms	324 KB	Output is correct
53	Correct	1 ms	340 KB	Output is correct
54	Correct	1 ms	324 KB	Output is correct
55	Correct	1 ms	340 KB	Output is correct
56	Correct	1 ms	212 KB	Output is correct
57	Correct	1 ms	324 KB	Output is correct
58	Correct	1 ms	468 KB	Output is correct
59	Correct	284 ms	37760 KB	Output is correct
60	Correct	350 ms	42032 KB	Output is correct
61	Correct	0 ms	324 KB	Output is correct
62	Correct	1 ms	212 KB	Output is correct
63	Correct	240 ms	34012 KB	Output is correct
64	Correct	2 ms	852 KB	Output is correct
65	Correct	9 ms	2800 KB	Output is correct
66	Correct	101 ms	21048 KB	Output is correct
67	Correct	411 ms	48928 KB	Output is correct
68	Correct	396 ms	49836 KB	Output is correct
69	Correct	6 ms	1620 KB	Output is correct
70	Correct	68 ms	14440 KB	Output is correct
71	Correct	233 ms	45712 KB	Output is correct
72	Correct	252 ms	44348 KB	Output is correct
73	Correct	63 ms	11344 KB	Output is correct
74	Correct	348 ms	40660 KB	Output is correct
75	Correct	19 ms	5200 KB	Output is correct
76	Correct	240 ms	45420 KB	Output is correct
77	Correct	244 ms	45484 KB	Output is correct
78	Correct	25 ms	5196 KB	Output is correct
79	Correct	387 ms	47124 KB	Output is correct
80	Correct	2 ms	596 KB	Output is correct
81	Correct	75 ms	14648 KB	Output is correct
82	Correct	299 ms	42988 KB	Output is correct
83	Correct	354 ms	40608 KB	Output is correct
84	Correct	346 ms	40644 KB	Output is correct
85	Correct	342 ms	40652 KB	Output is correct
86	Correct	354 ms	42036 KB	Output is correct
87	Correct	350 ms	42048 KB	Output is correct

Submission #705324

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