oj.uz

Submission #305452

# Submission time Handle Problem Language Result Execution time Memory
305452 2020-09-23T08:27:39 Z shahriarkhan Network (BOI15_net) C++14
100 / 100
 681 ms 45940 KB 
#include<bits/stdc++.h>
using namespace std ;

const int siz = 5e5 + 69 ;

vector<int> adj[siz] , ar ;

int deg[siz] ;

void dfs(int s , int p)
{
    if(deg[s]==1) ar.push_back(s) ;
    for(int t : adj[s])
    {
        if(t==p) continue ;
        dfs(t,s) ;
    }
}

int main()
{
    int n ;
    scanf("%d",&n) ;
    for(int i = 1 ; i < n ; ++i)
    {
        int u , v ;
        scanf("%d%d",&u,&v) ;
        adj[u].push_back(v) ;
        adj[v].push_back(u) ;
        ++deg[u] , ++deg[v] ;
    }
    dfs(1,0) ;
    int six = ar.size() ;
    printf("%d\n",(six+1)/2) ;
    int mid = (six+1)/2 ;
    for(int i = 0 ; i < mid ; ++i)
    {
        if((i+mid)<six) printf("%d %d\n",ar[i],ar[i+mid]) ;
        else printf("%d %d\n",ar[i],ar[six-1]) ;
    }
    return 0 ;
}

Compilation message

net.cpp: In function 'int main()':
net.cpp:23:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   23 |     scanf("%d",&n) ;
      |     ~~~~~^~~~~~~~~
net.cpp:27:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   27 |         scanf("%d%d",&u,&v) ;
      |         ~~~~~^~~~~~~~~~~~~~

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 12032 KB Output is correct
2 Correct 9 ms 12032 KB Output is correct
3 Correct 9 ms 12032 KB Output is correct
4 Correct 9 ms 12032 KB Output is correct
5 Correct 10 ms 12032 KB Output is correct
6 Correct 10 ms 12032 KB Output is correct
7 Correct 10 ms 12032 KB Output is correct
8 Correct 9 ms 12032 KB Output is correct
9 Correct 10 ms 12032 KB Output is correct
10 Correct 9 ms 12032 KB Output is correct
11 Correct 10 ms 12032 KB Output is correct
12 Correct 11 ms 12032 KB Output is correct
13 Correct 10 ms 12032 KB Output is correct
14 Correct 11 ms 12288 KB Output is correct
15 Correct 10 ms 12032 KB Output is correct
16 Correct 11 ms 12064 KB Output is correct
17 Correct 10 ms 12032 KB Output is correct
18 Correct 9 ms 12032 KB Output is correct
19 Correct 11 ms 12032 KB Output is correct
20 Correct 10 ms 12032 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 12032 KB Output is correct
2 Correct 9 ms 12032 KB Output is correct
3 Correct 9 ms 12032 KB Output is correct
4 Correct 9 ms 12032 KB Output is correct
5 Correct 10 ms 12032 KB Output is correct
6 Correct 10 ms 12032 KB Output is correct
7 Correct 10 ms 12032 KB Output is correct
8 Correct 9 ms 12032 KB Output is correct
9 Correct 10 ms 12032 KB Output is correct
10 Correct 9 ms 12032 KB Output is correct
11 Correct 10 ms 12032 KB Output is correct
12 Correct 11 ms 12032 KB Output is correct
13 Correct 10 ms 12032 KB Output is correct
14 Correct 11 ms 12288 KB Output is correct
15 Correct 10 ms 12032 KB Output is correct
16 Correct 11 ms 12064 KB Output is correct
17 Correct 10 ms 12032 KB Output is correct
18 Correct 9 ms 12032 KB Output is correct
19 Correct 11 ms 12032 KB Output is correct
20 Correct 10 ms 12032 KB Output is correct
21 Correct 10 ms 12032 KB Output is correct
22 Correct 11 ms 12160 KB Output is correct
23 Correct 11 ms 12160 KB Output is correct
24 Correct 10 ms 12160 KB Output is correct
25 Correct 11 ms 12160 KB Output is correct
26 Correct 11 ms 12160 KB Output is correct
27 Correct 10 ms 12160 KB Output is correct
28 Correct 11 ms 12160 KB Output is correct
29 Correct 11 ms 12160 KB Output is correct
30 Correct 10 ms 12032 KB Output is correct
31 Correct 11 ms 12160 KB Output is correct
32 Correct 10 ms 12192 KB Output is correct
33 Correct 10 ms 12032 KB Output is correct
34 Correct 9 ms 12032 KB Output is correct
35 Correct 10 ms 12032 KB Output is correct
36 Correct 10 ms 12032 KB Output is correct
37 Correct 12 ms 12160 KB Output is correct
38 Correct 10 ms 12160 KB Output is correct
39 Correct 10 ms 12032 KB Output is correct
40 Correct 10 ms 12032 KB Output is correct
41 Correct 11 ms 12032 KB Output is correct
42 Correct 10 ms 12032 KB Output is correct
43 Correct 10 ms 12160 KB Output is correct
44 Correct 10 ms 12032 KB Output is correct
45 Correct 11 ms 12032 KB Output is correct
46 Correct 10 ms 12160 KB Output is correct
47 Correct 10 ms 12032 KB Output is correct
48 Correct 10 ms 12032 KB Output is correct
49 Correct 12 ms 12160 KB Output is correct
50 Correct 10 ms 12032 KB Output is correct
51 Correct 11 ms 12032 KB Output is correct
52 Correct 11 ms 12032 KB Output is correct
53 Correct 10 ms 12160 KB Output is correct
54 Correct 9 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 11 ms 12160 KB Output is correct

Subtask #3
37.0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 12032 KB Output is correct
2 Correct 9 ms 12032 KB Output is correct
3 Correct 9 ms 12032 KB Output is correct
4 Correct 9 ms 12032 KB Output is correct
5 Correct 10 ms 12032 KB Output is correct
6 Correct 10 ms 12032 KB Output is correct
7 Correct 10 ms 12032 KB Output is correct
8 Correct 9 ms 12032 KB Output is correct
9 Correct 10 ms 12032 KB Output is correct
10 Correct 9 ms 12032 KB Output is correct
11 Correct 10 ms 12032 KB Output is correct
12 Correct 11 ms 12032 KB Output is correct
13 Correct 10 ms 12032 KB Output is correct
14 Correct 11 ms 12288 KB Output is correct
15 Correct 10 ms 12032 KB Output is correct
16 Correct 11 ms 12064 KB Output is correct
17 Correct 10 ms 12032 KB Output is correct
18 Correct 9 ms 12032 KB Output is correct
19 Correct 11 ms 12032 KB Output is correct
20 Correct 10 ms 12032 KB Output is correct
21 Correct 10 ms 12032 KB Output is correct
22 Correct 11 ms 12160 KB Output is correct
23 Correct 11 ms 12160 KB Output is correct
24 Correct 10 ms 12160 KB Output is correct
25 Correct 11 ms 12160 KB Output is correct
26 Correct 11 ms 12160 KB Output is correct
27 Correct 10 ms 12160 KB Output is correct
28 Correct 11 ms 12160 KB Output is correct
29 Correct 11 ms 12160 KB Output is correct
30 Correct 10 ms 12032 KB Output is correct
31 Correct 11 ms 12160 KB Output is correct
32 Correct 10 ms 12192 KB Output is correct
33 Correct 10 ms 12032 KB Output is correct
34 Correct 9 ms 12032 KB Output is correct
35 Correct 10 ms 12032 KB Output is correct
36 Correct 10 ms 12032 KB Output is correct
37 Correct 12 ms 12160 KB Output is correct
38 Correct 10 ms 12160 KB Output is correct
39 Correct 10 ms 12032 KB Output is correct
40 Correct 10 ms 12032 KB Output is correct
41 Correct 11 ms 12032 KB Output is correct
42 Correct 10 ms 12032 KB Output is correct
43 Correct 10 ms 12160 KB Output is correct
44 Correct 10 ms 12032 KB Output is correct
45 Correct 11 ms 12032 KB Output is correct
46 Correct 10 ms 12160 KB Output is correct
47 Correct 10 ms 12032 KB Output is correct
48 Correct 10 ms 12032 KB Output is correct
49 Correct 12 ms 12160 KB Output is correct
50 Correct 10 ms 12032 KB Output is correct
51 Correct 11 ms 12032 KB Output is correct
52 Correct 11 ms 12032 KB Output is correct
53 Correct 10 ms 12160 KB Output is correct
54 Correct 9 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 11 ms 12160 KB Output is correct
59 Correct 521 ms 34784 KB Output is correct
60 Correct 618 ms 36972 KB Output is correct
61 Correct 10 ms 12032 KB Output is correct
62 Correct 10 ms 12032 KB Output is correct
63 Correct 455 ms 32872 KB Output is correct
64 Correct 12 ms 12544 KB Output is correct
65 Correct 24 ms 14080 KB Output is correct
66 Correct 222 ms 28744 KB Output is correct
67 Correct 674 ms 45304 KB Output is correct
68 Correct 680 ms 45940 KB Output is correct
69 Correct 18 ms 13184 KB Output is correct
70 Correct 131 ms 21868 KB Output is correct
71 Correct 432 ms 39908 KB Output is correct
72 Correct 459 ms 39520 KB Output is correct
73 Correct 144 ms 19696 KB Output is correct
74 Correct 622 ms 35952 KB Output is correct
75 Correct 42 ms 15480 KB Output is correct
76 Correct 458 ms 39760 KB Output is correct
77 Correct 440 ms 40028 KB Output is correct
78 Correct 50 ms 15608 KB Output is correct
79 Correct 681 ms 43512 KB Output is correct
80 Correct 12 ms 12288 KB Output is correct
81 Correct 159 ms 22000 KB Output is correct
82 Correct 529 ms 37864 KB Output is correct
83 Correct 654 ms 35912 KB Output is correct
84 Correct 636 ms 35952 KB Output is correct
85 Correct 657 ms 36088 KB Output is correct
86 Correct 648 ms 37176 KB Output is correct
87 Correct 627 ms 36996 KB Output is correct