답안 #30470

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
30470 2017-07-23T12:23:36 Z sampriti Network (BOI15_net) C++14
63 / 100
509 ms 32100 KB
#include <iostream>
#include <algorithm>
#include <vector>

using namespace std;

vector<int> G[500001];
vector<int> leaves;

void dfs(int i, int p) {
  bool leaf = true;

  for(int u: G[i]) {
    if(u == p) continue;

    leaf = false;
    dfs(u, i);
  }

  if(leaf) leaves.push_back(i);
}

int main() {
  ios::sync_with_stdio(false); cin.tie(0);

  int N; cin >> N;

  for(int i = 0; i < N - 1; i++) {
    int a, b; cin >> a >> b;
    G[a].push_back(b);
    G[b].push_back(a);
  }

  dfs(1, 0);
  if(G[1].size() == 1) leaves.push_back(1);

  int ans = (leaves.size() + 1)/2;

  cout << ans << endl;

  for(int i = 0; i < ans; i++) {
    cout << leaves[i] << " " << leaves[i + leaves.size()/2] << endl;
  }
}
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 13896 KB Output is correct
2 Correct 0 ms 13896 KB Output is correct
3 Correct 3 ms 13896 KB Output is correct
4 Correct 0 ms 13896 KB Output is correct
5 Correct 0 ms 13896 KB Output is correct
6 Correct 3 ms 13896 KB Output is correct
7 Correct 3 ms 13896 KB Output is correct
8 Correct 6 ms 13896 KB Output is correct
9 Correct 3 ms 13896 KB Output is correct
10 Correct 3 ms 13896 KB Output is correct
11 Correct 0 ms 13896 KB Output is correct
12 Correct 3 ms 13896 KB Output is correct
13 Correct 3 ms 13896 KB Output is correct
14 Correct 0 ms 13896 KB Output is correct
15 Correct 3 ms 13896 KB Output is correct
16 Correct 0 ms 13896 KB Output is correct
17 Correct 6 ms 13896 KB Output is correct
18 Correct 6 ms 13896 KB Output is correct
19 Correct 3 ms 13896 KB Output is correct
20 Correct 0 ms 13896 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 13896 KB Output is correct
2 Correct 0 ms 13896 KB Output is correct
3 Correct 3 ms 13896 KB Output is correct
4 Correct 0 ms 13896 KB Output is correct
5 Correct 0 ms 13896 KB Output is correct
6 Correct 3 ms 13896 KB Output is correct
7 Correct 3 ms 13896 KB Output is correct
8 Correct 6 ms 13896 KB Output is correct
9 Correct 3 ms 13896 KB Output is correct
10 Correct 3 ms 13896 KB Output is correct
11 Correct 0 ms 13896 KB Output is correct
12 Correct 3 ms 13896 KB Output is correct
13 Correct 3 ms 13896 KB Output is correct
14 Correct 0 ms 13896 KB Output is correct
15 Correct 3 ms 13896 KB Output is correct
16 Correct 0 ms 13896 KB Output is correct
17 Correct 6 ms 13896 KB Output is correct
18 Correct 6 ms 13896 KB Output is correct
19 Correct 3 ms 13896 KB Output is correct
20 Correct 0 ms 13896 KB Output is correct
21 Correct 3 ms 13896 KB Output is correct
22 Correct 6 ms 13896 KB Output is correct
23 Correct 6 ms 13896 KB Output is correct
24 Correct 0 ms 13896 KB Output is correct
25 Correct 9 ms 13896 KB Output is correct
26 Correct 6 ms 13896 KB Output is correct
27 Correct 6 ms 13896 KB Output is correct
28 Correct 3 ms 13896 KB Output is correct
29 Correct 3 ms 13896 KB Output is correct
30 Correct 3 ms 13896 KB Output is correct
31 Correct 9 ms 13896 KB Output is correct
32 Correct 3 ms 13896 KB Output is correct
33 Correct 3 ms 13896 KB Output is correct
34 Correct 6 ms 13896 KB Output is correct
35 Correct 3 ms 13896 KB Output is correct
36 Correct 0 ms 13896 KB Output is correct
37 Correct 3 ms 13896 KB Output is correct
38 Correct 6 ms 13896 KB Output is correct
39 Correct 0 ms 13896 KB Output is correct
40 Correct 3 ms 13896 KB Output is correct
41 Correct 3 ms 13896 KB Output is correct
42 Correct 3 ms 13896 KB Output is correct
43 Correct 6 ms 13896 KB Output is correct
44 Correct 6 ms 13896 KB Output is correct
45 Correct 0 ms 13896 KB Output is correct
46 Correct 3 ms 13896 KB Output is correct
47 Correct 0 ms 13896 KB Output is correct
48 Correct 0 ms 13896 KB Output is correct
49 Correct 0 ms 13896 KB Output is correct
50 Correct 0 ms 13896 KB Output is correct
51 Correct 3 ms 13896 KB Output is correct
52 Correct 6 ms 13896 KB Output is correct
53 Correct 3 ms 13896 KB Output is correct
54 Correct 0 ms 13896 KB Output is correct
55 Correct 3 ms 13896 KB Output is correct
56 Correct 3 ms 13896 KB Output is correct
57 Correct 0 ms 13896 KB Output is correct
58 Correct 3 ms 13896 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 13896 KB Output is correct
2 Correct 0 ms 13896 KB Output is correct
3 Correct 3 ms 13896 KB Output is correct
4 Correct 0 ms 13896 KB Output is correct
5 Correct 0 ms 13896 KB Output is correct
6 Correct 3 ms 13896 KB Output is correct
7 Correct 3 ms 13896 KB Output is correct
8 Correct 6 ms 13896 KB Output is correct
9 Correct 3 ms 13896 KB Output is correct
10 Correct 3 ms 13896 KB Output is correct
11 Correct 0 ms 13896 KB Output is correct
12 Correct 3 ms 13896 KB Output is correct
13 Correct 3 ms 13896 KB Output is correct
14 Correct 0 ms 13896 KB Output is correct
15 Correct 3 ms 13896 KB Output is correct
16 Correct 0 ms 13896 KB Output is correct
17 Correct 6 ms 13896 KB Output is correct
18 Correct 6 ms 13896 KB Output is correct
19 Correct 3 ms 13896 KB Output is correct
20 Correct 0 ms 13896 KB Output is correct
21 Correct 3 ms 13896 KB Output is correct
22 Correct 6 ms 13896 KB Output is correct
23 Correct 6 ms 13896 KB Output is correct
24 Correct 0 ms 13896 KB Output is correct
25 Correct 9 ms 13896 KB Output is correct
26 Correct 6 ms 13896 KB Output is correct
27 Correct 6 ms 13896 KB Output is correct
28 Correct 3 ms 13896 KB Output is correct
29 Correct 3 ms 13896 KB Output is correct
30 Correct 3 ms 13896 KB Output is correct
31 Correct 9 ms 13896 KB Output is correct
32 Correct 3 ms 13896 KB Output is correct
33 Correct 3 ms 13896 KB Output is correct
34 Correct 6 ms 13896 KB Output is correct
35 Correct 3 ms 13896 KB Output is correct
36 Correct 0 ms 13896 KB Output is correct
37 Correct 3 ms 13896 KB Output is correct
38 Correct 6 ms 13896 KB Output is correct
39 Correct 0 ms 13896 KB Output is correct
40 Correct 3 ms 13896 KB Output is correct
41 Correct 3 ms 13896 KB Output is correct
42 Correct 3 ms 13896 KB Output is correct
43 Correct 6 ms 13896 KB Output is correct
44 Correct 6 ms 13896 KB Output is correct
45 Correct 0 ms 13896 KB Output is correct
46 Correct 3 ms 13896 KB Output is correct
47 Correct 0 ms 13896 KB Output is correct
48 Correct 0 ms 13896 KB Output is correct
49 Correct 0 ms 13896 KB Output is correct
50 Correct 0 ms 13896 KB Output is correct
51 Correct 3 ms 13896 KB Output is correct
52 Correct 6 ms 13896 KB Output is correct
53 Correct 3 ms 13896 KB Output is correct
54 Correct 0 ms 13896 KB Output is correct
55 Correct 3 ms 13896 KB Output is correct
56 Correct 3 ms 13896 KB Output is correct
57 Correct 0 ms 13896 KB Output is correct
58 Correct 3 ms 13896 KB Output is correct
59 Runtime error 509 ms 32100 KB Execution timed out (wall clock limit exceeded)
60 Halted 0 ms 0 KB -