oj.uz

Submission #994590

# Submission time Handle Problem Language Result Execution time Memory
994590 2024-06-08T02:05:07 Z guagua0407 Network (BOI15_net) C++17
100 / 100
 373 ms 47396 KB 
//#pragma GCC optimize("O3")
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<int,int>
#define f first
#define s second
#define all(x) x.begin(),x.end()
#define _ ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);

int dx[4]={0,0,1,-1};
int dy[4]={1,-1,0,0};

void setIO(string s) {
    freopen((s + ".in").c_str(), "r", stdin);
    freopen((s + ".out").c_str(), "w", stdout);
}

const int mxn=5e5+5;
vector<int> adj[mxn];
int deg[mxn];
vector<int> vec;

void dfs(int v,int p=-1){
    for(auto u:adj[v]){
        if(u==p) continue;
        deg[v]++;
        deg[u]++;
        dfs(u,v);
    }
    if(deg[v]==1) vec.push_back(v);
}

int main() {_
    int n;
    cin>>n;
    for(int i=0;i<n-1;i++){
        int a,b;
        cin>>a>>b;
        adj[a].push_back(b);
        adj[b].push_back(a);
    }
    dfs(1);
    int ans=((int)vec.size()+1)/2;
    cout<<ans<<'\n';
    for(int i=0;i<ans;i++){
        cout<<vec[i]<<' '<<vec[(i+(int)vec.size()/2)]<<'\n';
    }
    return 0;
}
//maybe its multiset not set
//yeeorz
//laborz

Compilation message

net.cpp: In function 'void setIO(std::string)':
net.cpp:15:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   15 |     freopen((s + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
net.cpp:16:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   16 |     freopen((s + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 13916 KB Output is correct
2 Correct 4 ms 13916 KB Output is correct
3 Correct 3 ms 13916 KB Output is correct
4 Correct 3 ms 13916 KB Output is correct
5 Correct 3 ms 13916 KB Output is correct
6 Correct 3 ms 13916 KB Output is correct
7 Correct 4 ms 13912 KB Output is correct
8 Correct 5 ms 13916 KB Output is correct
9 Correct 3 ms 13916 KB Output is correct
10 Correct 3 ms 13912 KB Output is correct
11 Correct 3 ms 13916 KB Output is correct
12 Correct 3 ms 13916 KB Output is correct
13 Correct 4 ms 13872 KB Output is correct
14 Correct 3 ms 13912 KB Output is correct
15 Correct 3 ms 13916 KB Output is correct
16 Correct 3 ms 13916 KB Output is correct
17 Correct 4 ms 13916 KB Output is correct
18 Correct 4 ms 13912 KB Output is correct
19 Correct 3 ms 13916 KB Output is correct
20 Correct 2 ms 13916 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 13916 KB Output is correct
2 Correct 4 ms 13916 KB Output is correct
3 Correct 3 ms 13916 KB Output is correct
4 Correct 3 ms 13916 KB Output is correct
5 Correct 3 ms 13916 KB Output is correct
6 Correct 3 ms 13916 KB Output is correct
7 Correct 4 ms 13912 KB Output is correct
8 Correct 5 ms 13916 KB Output is correct
9 Correct 3 ms 13916 KB Output is correct
10 Correct 3 ms 13912 KB Output is correct
11 Correct 3 ms 13916 KB Output is correct
12 Correct 3 ms 13916 KB Output is correct
13 Correct 4 ms 13872 KB Output is correct
14 Correct 3 ms 13912 KB Output is correct
15 Correct 3 ms 13916 KB Output is correct
16 Correct 3 ms 13916 KB Output is correct
17 Correct 4 ms 13916 KB Output is correct
18 Correct 4 ms 13912 KB Output is correct
19 Correct 3 ms 13916 KB Output is correct
20 Correct 2 ms 13916 KB Output is correct
21 Correct 4 ms 13912 KB Output is correct
22 Correct 3 ms 13916 KB Output is correct
23 Correct 3 ms 13912 KB Output is correct
24 Correct 3 ms 13916 KB Output is correct
25 Correct 4 ms 13912 KB Output is correct
26 Correct 4 ms 13916 KB Output is correct
27 Correct 4 ms 13912 KB Output is correct
28 Correct 4 ms 13912 KB Output is correct
29 Correct 4 ms 14016 KB Output is correct
30 Correct 3 ms 13912 KB Output is correct
31 Correct 5 ms 13916 KB Output is correct
32 Correct 3 ms 13916 KB Output is correct
33 Correct 3 ms 13972 KB Output is correct
34 Correct 3 ms 13916 KB Output is correct
35 Correct 3 ms 13916 KB Output is correct
36 Correct 3 ms 13916 KB Output is correct
37 Correct 4 ms 13916 KB Output is correct
38 Correct 4 ms 13912 KB Output is correct
39 Correct 4 ms 13916 KB Output is correct
40 Correct 3 ms 13912 KB Output is correct
41 Correct 4 ms 13752 KB Output is correct
42 Correct 3 ms 13916 KB Output is correct
43 Correct 3 ms 13916 KB Output is correct
44 Correct 3 ms 13912 KB Output is correct
45 Correct 5 ms 13912 KB Output is correct
46 Correct 3 ms 13912 KB Output is correct
47 Correct 2 ms 13916 KB Output is correct
48 Correct 3 ms 13916 KB Output is correct
49 Correct 3 ms 13912 KB Output is correct
50 Correct 3 ms 13916 KB Output is correct
51 Correct 3 ms 13916 KB Output is correct
52 Correct 3 ms 13912 KB Output is correct
53 Correct 3 ms 13916 KB Output is correct
54 Correct 3 ms 13916 KB Output is correct
55 Correct 3 ms 13916 KB Output is correct
56 Correct 5 ms 13916 KB Output is correct
57 Correct 5 ms 13916 KB Output is correct
58 Correct 4 ms 13916 KB Output is correct

Subtask #3
37.0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 13916 KB Output is correct
2 Correct 4 ms 13916 KB Output is correct
3 Correct 3 ms 13916 KB Output is correct
4 Correct 3 ms 13916 KB Output is correct
5 Correct 3 ms 13916 KB Output is correct
6 Correct 3 ms 13916 KB Output is correct
7 Correct 4 ms 13912 KB Output is correct
8 Correct 5 ms 13916 KB Output is correct
9 Correct 3 ms 13916 KB Output is correct
10 Correct 3 ms 13912 KB Output is correct
11 Correct 3 ms 13916 KB Output is correct
12 Correct 3 ms 13916 KB Output is correct
13 Correct 4 ms 13872 KB Output is correct
14 Correct 3 ms 13912 KB Output is correct
15 Correct 3 ms 13916 KB Output is correct
16 Correct 3 ms 13916 KB Output is correct
17 Correct 4 ms 13916 KB Output is correct
18 Correct 4 ms 13912 KB Output is correct
19 Correct 3 ms 13916 KB Output is correct
20 Correct 2 ms 13916 KB Output is correct
21 Correct 4 ms 13912 KB Output is correct
22 Correct 3 ms 13916 KB Output is correct
23 Correct 3 ms 13912 KB Output is correct
24 Correct 3 ms 13916 KB Output is correct
25 Correct 4 ms 13912 KB Output is correct
26 Correct 4 ms 13916 KB Output is correct
27 Correct 4 ms 13912 KB Output is correct
28 Correct 4 ms 13912 KB Output is correct
29 Correct 4 ms 14016 KB Output is correct
30 Correct 3 ms 13912 KB Output is correct
31 Correct 5 ms 13916 KB Output is correct
32 Correct 3 ms 13916 KB Output is correct
33 Correct 3 ms 13972 KB Output is correct
34 Correct 3 ms 13916 KB Output is correct
35 Correct 3 ms 13916 KB Output is correct
36 Correct 3 ms 13916 KB Output is correct
37 Correct 4 ms 13916 KB Output is correct
38 Correct 4 ms 13912 KB Output is correct
39 Correct 4 ms 13916 KB Output is correct
40 Correct 3 ms 13912 KB Output is correct
41 Correct 4 ms 13752 KB Output is correct
42 Correct 3 ms 13916 KB Output is correct
43 Correct 3 ms 13916 KB Output is correct
44 Correct 3 ms 13912 KB Output is correct
45 Correct 5 ms 13912 KB Output is correct
46 Correct 3 ms 13912 KB Output is correct
47 Correct 2 ms 13916 KB Output is correct
48 Correct 3 ms 13916 KB Output is correct
49 Correct 3 ms 13912 KB Output is correct
50 Correct 3 ms 13916 KB Output is correct
51 Correct 3 ms 13916 KB Output is correct
52 Correct 3 ms 13912 KB Output is correct
53 Correct 3 ms 13916 KB Output is correct
54 Correct 3 ms 13916 KB Output is correct
55 Correct 3 ms 13916 KB Output is correct
56 Correct 5 ms 13916 KB Output is correct
57 Correct 5 ms 13916 KB Output is correct
58 Correct 4 ms 13916 KB Output is correct
59 Correct 247 ms 32060 KB Output is correct
60 Correct 229 ms 34212 KB Output is correct
61 Correct 4 ms 13916 KB Output is correct
62 Correct 4 ms 13912 KB Output is correct
63 Correct 204 ms 30196 KB Output is correct
64 Correct 4 ms 14428 KB Output is correct
65 Correct 9 ms 15832 KB Output is correct
66 Correct 94 ms 30288 KB Output is correct
67 Correct 373 ms 46420 KB Output is correct
68 Correct 322 ms 47396 KB Output is correct
69 Correct 7 ms 14680 KB Output is correct
70 Correct 57 ms 21236 KB Output is correct
71 Correct 221 ms 37060 KB Output is correct
72 Correct 208 ms 36448 KB Output is correct
73 Correct 61 ms 19488 KB Output is correct
74 Correct 326 ms 32952 KB Output is correct
75 Correct 18 ms 16600 KB Output is correct
76 Correct 209 ms 36784 KB Output is correct
77 Correct 253 ms 37248 KB Output is correct
78 Correct 25 ms 16980 KB Output is correct
79 Correct 309 ms 44076 KB Output is correct
80 Correct 5 ms 14168 KB Output is correct
81 Correct 85 ms 21320 KB Output is correct
82 Correct 261 ms 35016 KB Output is correct
83 Correct 236 ms 32964 KB Output is correct
84 Correct 293 ms 32960 KB Output is correct
85 Correct 327 ms 32964 KB Output is correct
86 Correct 254 ms 34208 KB Output is correct
87 Correct 300 ms 34172 KB Output is correct