oj.uz

Submission #32316

# Submission time Handle Problem Language Result Execution time Memory
32316 2017-10-08T14:22:33 Z dqhungdl Network (BOI15_net) C++14
100 / 100
 766 ms 38724 KB 
#include <bits/stdc++.h>
using namespace std;

int n;
bool Free[500005];
vector<int> V,g[500005];

void DFS(int u)
{
    Free[u]=true;
    if(g[u].size()==1)
        V.push_back(u);
    for(int i=0;i<g[u].size();i++)
        if(Free[g[u][i]]==false)
            DFS(g[u][i]);
}

int main()
{
    //ios_base::sync_with_stdio(false);
    //freopen("NET.INP","r",stdin);
    scanf("%d",&n);
    int u,v;
    for(int i=1;i<n;i++)
    {
        scanf("%d%d",&u,&v);
        g[u].push_back(v);
        g[v].push_back(u);
    }
    DFS(1);
    int res=(V.size()+1)/2;
    printf("%d\n",res);
    for(int i=0;i<res;i++)
        if(i+V.size()/2<V.size())
            printf("%d %d\n",V[i],V[i+V.size()/2]);
}

Compilation message

net.cpp: In function 'void DFS(int)':
net.cpp:13:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<g[u].size();i++)
                  ^
net.cpp: In function 'int main()':
net.cpp:22:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&n);
                   ^
net.cpp:26:28: 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 3 ms 14220 KB Output is correct
2 Correct 3 ms 14220 KB Output is correct
3 Correct 3 ms 14220 KB Output is correct
4 Correct 3 ms 14220 KB Output is correct
5 Correct 0 ms 14220 KB Output is correct
6 Correct 0 ms 14220 KB Output is correct
7 Correct 6 ms 14220 KB Output is correct
8 Correct 3 ms 14220 KB Output is correct
9 Correct 0 ms 14220 KB Output is correct
10 Correct 0 ms 14220 KB Output is correct
11 Correct 0 ms 14220 KB Output is correct
12 Correct 3 ms 14220 KB Output is correct
13 Correct 0 ms 14220 KB Output is correct
14 Correct 3 ms 14220 KB Output is correct
15 Correct 3 ms 14220 KB Output is correct
16 Correct 3 ms 14220 KB Output is correct
17 Correct 3 ms 14220 KB Output is correct
18 Correct 3 ms 14220 KB Output is correct
19 Correct 3 ms 14220 KB Output is correct
20 Correct 3 ms 14220 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 14220 KB Output is correct
2 Correct 3 ms 14220 KB Output is correct
3 Correct 3 ms 14220 KB Output is correct
4 Correct 3 ms 14220 KB Output is correct
5 Correct 0 ms 14220 KB Output is correct
6 Correct 0 ms 14220 KB Output is correct
7 Correct 6 ms 14220 KB Output is correct
8 Correct 3 ms 14220 KB Output is correct
9 Correct 0 ms 14220 KB Output is correct
10 Correct 0 ms 14220 KB Output is correct
11 Correct 0 ms 14220 KB Output is correct
12 Correct 3 ms 14220 KB Output is correct
13 Correct 0 ms 14220 KB Output is correct
14 Correct 3 ms 14220 KB Output is correct
15 Correct 3 ms 14220 KB Output is correct
16 Correct 3 ms 14220 KB Output is correct
17 Correct 3 ms 14220 KB Output is correct
18 Correct 3 ms 14220 KB Output is correct
19 Correct 3 ms 14220 KB Output is correct
20 Correct 3 ms 14220 KB Output is correct
21 Correct 0 ms 14220 KB Output is correct
22 Correct 3 ms 14352 KB Output is correct
23 Correct 6 ms 14352 KB Output is correct
24 Correct 9 ms 14352 KB Output is correct
25 Correct 0 ms 14352 KB Output is correct
26 Correct 6 ms 14352 KB Output is correct
27 Correct 3 ms 14352 KB Output is correct
28 Correct 6 ms 14352 KB Output is correct
29 Correct 6 ms 14352 KB Output is correct
30 Correct 0 ms 14220 KB Output is correct
31 Correct 3 ms 14352 KB Output is correct
32 Correct 3 ms 14220 KB Output is correct
33 Correct 0 ms 14220 KB Output is correct
34 Correct 3 ms 14220 KB Output is correct
35 Correct 0 ms 14220 KB Output is correct
36 Correct 6 ms 14220 KB Output is correct
37 Correct 3 ms 14220 KB Output is correct
38 Correct 6 ms 14220 KB Output is correct
39 Correct 0 ms 14220 KB Output is correct
40 Correct 0 ms 14220 KB Output is correct
41 Correct 3 ms 14220 KB Output is correct
42 Correct 0 ms 14220 KB Output is correct
43 Correct 3 ms 14220 KB Output is correct
44 Correct 0 ms 14220 KB Output is correct
45 Correct 3 ms 14220 KB Output is correct
46 Correct 0 ms 14220 KB Output is correct
47 Correct 0 ms 14220 KB Output is correct
48 Correct 3 ms 14220 KB Output is correct
49 Correct 6 ms 14220 KB Output is correct
50 Correct 6 ms 14220 KB Output is correct
51 Correct 3 ms 14220 KB Output is correct
52 Correct 0 ms 14220 KB Output is correct
53 Correct 3 ms 14220 KB Output is correct
54 Correct 3 ms 14220 KB Output is correct
55 Correct 6 ms 14220 KB Output is correct
56 Correct 0 ms 14220 KB Output is correct
57 Correct 0 ms 14220 KB Output is correct
58 Correct 6 ms 14352 KB Output is correct

Subtask #3
37.0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 14220 KB Output is correct
2 Correct 3 ms 14220 KB Output is correct
3 Correct 3 ms 14220 KB Output is correct
4 Correct 3 ms 14220 KB Output is correct
5 Correct 0 ms 14220 KB Output is correct
6 Correct 0 ms 14220 KB Output is correct
7 Correct 6 ms 14220 KB Output is correct
8 Correct 3 ms 14220 KB Output is correct
9 Correct 0 ms 14220 KB Output is correct
10 Correct 0 ms 14220 KB Output is correct
11 Correct 0 ms 14220 KB Output is correct
12 Correct 3 ms 14220 KB Output is correct
13 Correct 0 ms 14220 KB Output is correct
14 Correct 3 ms 14220 KB Output is correct
15 Correct 3 ms 14220 KB Output is correct
16 Correct 3 ms 14220 KB Output is correct
17 Correct 3 ms 14220 KB Output is correct
18 Correct 3 ms 14220 KB Output is correct
19 Correct 3 ms 14220 KB Output is correct
20 Correct 3 ms 14220 KB Output is correct
21 Correct 0 ms 14220 KB Output is correct
22 Correct 3 ms 14352 KB Output is correct
23 Correct 6 ms 14352 KB Output is correct
24 Correct 9 ms 14352 KB Output is correct
25 Correct 0 ms 14352 KB Output is correct
26 Correct 6 ms 14352 KB Output is correct
27 Correct 3 ms 14352 KB Output is correct
28 Correct 6 ms 14352 KB Output is correct
29 Correct 6 ms 14352 KB Output is correct
30 Correct 0 ms 14220 KB Output is correct
31 Correct 3 ms 14352 KB Output is correct
32 Correct 3 ms 14220 KB Output is correct
33 Correct 0 ms 14220 KB Output is correct
34 Correct 3 ms 14220 KB Output is correct
35 Correct 0 ms 14220 KB Output is correct
36 Correct 6 ms 14220 KB Output is correct
37 Correct 3 ms 14220 KB Output is correct
38 Correct 6 ms 14220 KB Output is correct
39 Correct 0 ms 14220 KB Output is correct
40 Correct 0 ms 14220 KB Output is correct
41 Correct 3 ms 14220 KB Output is correct
42 Correct 0 ms 14220 KB Output is correct
43 Correct 3 ms 14220 KB Output is correct
44 Correct 0 ms 14220 KB Output is correct
45 Correct 3 ms 14220 KB Output is correct
46 Correct 0 ms 14220 KB Output is correct
47 Correct 0 ms 14220 KB Output is correct
48 Correct 3 ms 14220 KB Output is correct
49 Correct 6 ms 14220 KB Output is correct
50 Correct 6 ms 14220 KB Output is correct
51 Correct 3 ms 14220 KB Output is correct
52 Correct 0 ms 14220 KB Output is correct
53 Correct 3 ms 14220 KB Output is correct
54 Correct 3 ms 14220 KB Output is correct
55 Correct 6 ms 14220 KB Output is correct
56 Correct 0 ms 14220 KB Output is correct
57 Correct 0 ms 14220 KB Output is correct
58 Correct 6 ms 14352 KB Output is correct
59 Correct 559 ms 32468 KB Output is correct
60 Correct 629 ms 33732 KB Output is correct
61 Correct 0 ms 14220 KB Output is correct
62 Correct 6 ms 14220 KB Output is correct
63 Correct 513 ms 30392 KB Output is correct
64 Correct 3 ms 14384 KB Output is correct
65 Correct 13 ms 15456 KB Output is correct
66 Correct 213 ms 25076 KB Output is correct
67 Correct 756 ms 38048 KB Output is correct
68 Correct 746 ms 38724 KB Output is correct
69 Correct 13 ms 14956 KB Output is correct
70 Correct 113 ms 22376 KB Output is correct
71 Correct 439 ms 36072 KB Output is correct
72 Correct 453 ms 36072 KB Output is correct
73 Correct 119 ms 19576 KB Output is correct
74 Correct 646 ms 32016 KB Output is correct
75 Correct 33 ms 16684 KB Output is correct
76 Correct 443 ms 35056 KB Output is correct
77 Correct 406 ms 35056 KB Output is correct
78 Correct 39 ms 16444 KB Output is correct
79 Correct 766 ms 36884 KB Output is correct
80 Correct 3 ms 14352 KB Output is correct
81 Correct 156 ms 21248 KB Output is correct
82 Correct 516 ms 34300 KB Output is correct
83 Correct 616 ms 32016 KB Output is correct
84 Correct 609 ms 32016 KB Output is correct
85 Correct 706 ms 32016 KB Output is correct
86 Correct 633 ms 33736 KB Output is correct
87 Correct 566 ms 33736 KB Output is correct