답안 #96949 :: oj.uz

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
96949	2019-02-12T20:10:14 Z	dalgerok	Network (BOI15_net)	C++14	100 / 100	750 ms	65728 KB

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


const int N = 5e5 + 5;



int n, sz, a[N];
vector < int > g[N];

void dfs(int v, int pr = -1){
    for(int to : g[v]){
        if(to != pr){
            dfs(to, v);
        }
    }
    if((int)g[v].size() == 1){
        a[++sz] = v;
    }
}

int main(){
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    cin >> n;
    for(int i = 1; i < n; i++){
        int x, y;
        cin >> x >> y;
        g[x].push_back(y);
        g[y].push_back(x);
    }
    int rt = -1;
    for(int i = 1; i <= n; i++){
        if((int)g[i].size() > 1){
            rt = i;
        }
    }
    dfs(rt);
    int ans = (sz + 1) / 2;
    cout << ans << "\n";
    for(int i = 1; i < ans; i++){
        cout << a[i] << " " << a[i + ans] << "\n";
    }
    if(sz & 1){
        cout << a[1] << " " << a[ans] << "\n";
    }
    else{
        cout << a[sz] << " " << a[ans];
    }
}

Subtask #1
18.0 / 18.0

#	결과	실행 시간	메모리	Grader output
1	Correct	13 ms	12160 KB	Output is correct
2	Correct	12 ms	12032 KB	Output is correct
3	Correct	13 ms	12160 KB	Output is correct
4	Correct	13 ms	12160 KB	Output is correct
5	Correct	15 ms	12160 KB	Output is correct
6	Correct	14 ms	12032 KB	Output is correct
7	Correct	11 ms	12032 KB	Output is correct
8	Correct	14 ms	12160 KB	Output is correct
9	Correct	14 ms	12160 KB	Output is correct
10	Correct	14 ms	12032 KB	Output is correct
11	Correct	13 ms	12032 KB	Output is correct
12	Correct	14 ms	12032 KB	Output is correct
13	Correct	14 ms	12160 KB	Output is correct
14	Correct	13 ms	12032 KB	Output is correct
15	Correct	12 ms	12032 KB	Output is correct
16	Correct	14 ms	12160 KB	Output is correct
17	Correct	12 ms	12160 KB	Output is correct
18	Correct	12 ms	12160 KB	Output is correct
19	Correct	12 ms	12032 KB	Output is correct
20	Correct	12 ms	12160 KB	Output is correct

Subtask #2
45.0 / 45.0

#	결과	실행 시간	메모리	Grader output
1	Correct	13 ms	12160 KB	Output is correct
2	Correct	12 ms	12032 KB	Output is correct
3	Correct	13 ms	12160 KB	Output is correct
4	Correct	13 ms	12160 KB	Output is correct
5	Correct	15 ms	12160 KB	Output is correct
6	Correct	14 ms	12032 KB	Output is correct
7	Correct	11 ms	12032 KB	Output is correct
8	Correct	14 ms	12160 KB	Output is correct
9	Correct	14 ms	12160 KB	Output is correct
10	Correct	14 ms	12032 KB	Output is correct
11	Correct	13 ms	12032 KB	Output is correct
12	Correct	14 ms	12032 KB	Output is correct
13	Correct	14 ms	12160 KB	Output is correct
14	Correct	13 ms	12032 KB	Output is correct
15	Correct	12 ms	12032 KB	Output is correct
16	Correct	14 ms	12160 KB	Output is correct
17	Correct	12 ms	12160 KB	Output is correct
18	Correct	12 ms	12160 KB	Output is correct
19	Correct	12 ms	12032 KB	Output is correct
20	Correct	12 ms	12160 KB	Output is correct
21	Correct	13 ms	12160 KB	Output is correct
22	Correct	13 ms	12160 KB	Output is correct
23	Correct	13 ms	12160 KB	Output is correct
24	Correct	13 ms	12160 KB	Output is correct
25	Correct	13 ms	12160 KB	Output is correct
26	Correct	13 ms	12160 KB	Output is correct
27	Correct	13 ms	12288 KB	Output is correct
28	Correct	14 ms	12160 KB	Output is correct
29	Correct	15 ms	12160 KB	Output is correct
30	Correct	12 ms	12160 KB	Output is correct
31	Correct	16 ms	12288 KB	Output is correct
32	Correct	14 ms	12032 KB	Output is correct
33	Correct	14 ms	12032 KB	Output is correct
34	Correct	14 ms	12160 KB	Output is correct
35	Correct	16 ms	12160 KB	Output is correct
36	Correct	15 ms	12032 KB	Output is correct
37	Correct	15 ms	12160 KB	Output is correct
38	Correct	14 ms	12160 KB	Output is correct
39	Correct	13 ms	12032 KB	Output is correct
40	Correct	13 ms	12176 KB	Output is correct
41	Correct	14 ms	12152 KB	Output is correct
42	Correct	13 ms	12160 KB	Output is correct
43	Correct	12 ms	12160 KB	Output is correct
44	Correct	16 ms	12160 KB	Output is correct
45	Correct	15 ms	12160 KB	Output is correct
46	Correct	15 ms	12160 KB	Output is correct
47	Correct	13 ms	12160 KB	Output is correct
48	Correct	12 ms	12160 KB	Output is correct
49	Correct	12 ms	12160 KB	Output is correct
50	Correct	13 ms	12160 KB	Output is correct
51	Correct	13 ms	12160 KB	Output is correct
52	Correct	12 ms	12160 KB	Output is correct
53	Correct	12 ms	12160 KB	Output is correct
54	Correct	11 ms	12032 KB	Output is correct
55	Correct	17 ms	12160 KB	Output is correct
56	Correct	14 ms	12032 KB	Output is correct
57	Correct	14 ms	12160 KB	Output is correct
58	Correct	14 ms	12416 KB	Output is correct

Subtask #3
37.0 / 37.0

#	결과	실행 시간	메모리	Grader output
1	Correct	13 ms	12160 KB	Output is correct
2	Correct	12 ms	12032 KB	Output is correct
3	Correct	13 ms	12160 KB	Output is correct
4	Correct	13 ms	12160 KB	Output is correct
5	Correct	15 ms	12160 KB	Output is correct
6	Correct	14 ms	12032 KB	Output is correct
7	Correct	11 ms	12032 KB	Output is correct
8	Correct	14 ms	12160 KB	Output is correct
9	Correct	14 ms	12160 KB	Output is correct
10	Correct	14 ms	12032 KB	Output is correct
11	Correct	13 ms	12032 KB	Output is correct
12	Correct	14 ms	12032 KB	Output is correct
13	Correct	14 ms	12160 KB	Output is correct
14	Correct	13 ms	12032 KB	Output is correct
15	Correct	12 ms	12032 KB	Output is correct
16	Correct	14 ms	12160 KB	Output is correct
17	Correct	12 ms	12160 KB	Output is correct
18	Correct	12 ms	12160 KB	Output is correct
19	Correct	12 ms	12032 KB	Output is correct
20	Correct	12 ms	12160 KB	Output is correct
21	Correct	13 ms	12160 KB	Output is correct
22	Correct	13 ms	12160 KB	Output is correct
23	Correct	13 ms	12160 KB	Output is correct
24	Correct	13 ms	12160 KB	Output is correct
25	Correct	13 ms	12160 KB	Output is correct
26	Correct	13 ms	12160 KB	Output is correct
27	Correct	13 ms	12288 KB	Output is correct
28	Correct	14 ms	12160 KB	Output is correct
29	Correct	15 ms	12160 KB	Output is correct
30	Correct	12 ms	12160 KB	Output is correct
31	Correct	16 ms	12288 KB	Output is correct
32	Correct	14 ms	12032 KB	Output is correct
33	Correct	14 ms	12032 KB	Output is correct
34	Correct	14 ms	12160 KB	Output is correct
35	Correct	16 ms	12160 KB	Output is correct
36	Correct	15 ms	12032 KB	Output is correct
37	Correct	15 ms	12160 KB	Output is correct
38	Correct	14 ms	12160 KB	Output is correct
39	Correct	13 ms	12032 KB	Output is correct
40	Correct	13 ms	12176 KB	Output is correct
41	Correct	14 ms	12152 KB	Output is correct
42	Correct	13 ms	12160 KB	Output is correct
43	Correct	12 ms	12160 KB	Output is correct
44	Correct	16 ms	12160 KB	Output is correct
45	Correct	15 ms	12160 KB	Output is correct
46	Correct	15 ms	12160 KB	Output is correct
47	Correct	13 ms	12160 KB	Output is correct
48	Correct	12 ms	12160 KB	Output is correct
49	Correct	12 ms	12160 KB	Output is correct
50	Correct	13 ms	12160 KB	Output is correct
51	Correct	13 ms	12160 KB	Output is correct
52	Correct	12 ms	12160 KB	Output is correct
53	Correct	12 ms	12160 KB	Output is correct
54	Correct	11 ms	12032 KB	Output is correct
55	Correct	17 ms	12160 KB	Output is correct
56	Correct	14 ms	12032 KB	Output is correct
57	Correct	14 ms	12160 KB	Output is correct
58	Correct	14 ms	12416 KB	Output is correct
59	Correct	484 ms	35940 KB	Output is correct
60	Correct	590 ms	38720 KB	Output is correct
61	Correct	12 ms	12132 KB	Output is correct
62	Correct	13 ms	12032 KB	Output is correct
63	Correct	341 ms	33584 KB	Output is correct
64	Correct	16 ms	12544 KB	Output is correct
65	Correct	27 ms	14044 KB	Output is correct
66	Correct	213 ms	27000 KB	Output is correct
67	Correct	628 ms	65728 KB	Output is correct
68	Correct	750 ms	56184 KB	Output is correct
69	Correct	22 ms	12920 KB	Output is correct
70	Correct	123 ms	21200 KB	Output is correct
71	Correct	398 ms	41700 KB	Output is correct
72	Correct	423 ms	40636 KB	Output is correct
73	Correct	151 ms	18972 KB	Output is correct
74	Correct	664 ms	37780 KB	Output is correct
75	Correct	35 ms	15224 KB	Output is correct
76	Correct	361 ms	41568 KB	Output is correct
77	Correct	371 ms	41560 KB	Output is correct
78	Correct	42 ms	15736 KB	Output is correct
79	Correct	653 ms	48820 KB	Output is correct
80	Correct	13 ms	12288 KB	Output is correct
81	Correct	147 ms	21272 KB	Output is correct
82	Correct	518 ms	39408 KB	Output is correct
83	Correct	490 ms	37772 KB	Output is correct
84	Correct	602 ms	37624 KB	Output is correct
85	Correct	614 ms	37624 KB	Output is correct
86	Correct	587 ms	38844 KB	Output is correct
87	Correct	602 ms	38648 KB	Output is correct

답안 #96949

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