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Submission #311448

# Submission time Handle Problem Language Result Execution time Memory
311448 2020-10-10T08:48:20 Z vipghn2003 Network (BOI15_net) C++14
0 / 100
 10 ms 12032 KB 
#include<bits/stdc++.h>

using namespace std;

const int N=5e5+5;
int n;
vector<int>leaf;
vector<int>adj[N];

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cin>>n;
    for(int i=1;i<n;i++)
    {
        int u,v;
        cin>>u>>v;
        adj[u].push_back(v);
        adj[v].push_back(u);
    }
    for(int i=1;i<=n;i++) if(adj[i].size()==1) leaf.push_back(i);
    cout<<(leaf.size()+1)/2<<'\n';
    for(int i=0;i+1<leaf.size();i+=2) cout<<leaf[i]<<' '<<leaf[i+1]<<'\n';
    if(leaf.size()%2) cout<<leaf.back()<<' '<<leaf[0]<<'\n';
}

Compilation message

net.cpp: In function 'int main()':
net.cpp:24:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |     for(int i=0;i+1<leaf.size();i+=2) cout<<leaf[i]<<' '<<leaf[i+1]<<'\n';
      |                 ~~~^~~~~~~~~~~~

Subtask #1
0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 12032 KB Output is correct
2 Correct 8 ms 12032 KB Output is correct
3 Correct 10 ms 12032 KB Output is correct
4 Correct 9 ms 12032 KB Output is correct
5 Correct 8 ms 12032 KB Output is correct
6 Correct 8 ms 12032 KB Output is correct
7 Correct 8 ms 12032 KB Output is correct
8 Correct 9 ms 12032 KB Output is correct
9 Correct 9 ms 12032 KB Output is correct
10 Incorrect 8 ms 12032 KB Breaking single line is causing network to disconnect.
11 Halted 0 ms 0 KB -

Subtask #2
0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 12032 KB Output is correct
2 Correct 8 ms 12032 KB Output is correct
3 Correct 10 ms 12032 KB Output is correct
4 Correct 9 ms 12032 KB Output is correct
5 Correct 8 ms 12032 KB Output is correct
6 Correct 8 ms 12032 KB Output is correct
7 Correct 8 ms 12032 KB Output is correct
8 Correct 9 ms 12032 KB Output is correct
9 Correct 9 ms 12032 KB Output is correct
10 Incorrect 8 ms 12032 KB Breaking single line is causing network to disconnect.
11 Halted 0 ms 0 KB -

Subtask #3
0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 12032 KB Output is correct
2 Correct 8 ms 12032 KB Output is correct
3 Correct 10 ms 12032 KB Output is correct
4 Correct 9 ms 12032 KB Output is correct
5 Correct 8 ms 12032 KB Output is correct
6 Correct 8 ms 12032 KB Output is correct
7 Correct 8 ms 12032 KB Output is correct
8 Correct 9 ms 12032 KB Output is correct
9 Correct 9 ms 12032 KB Output is correct
10 Incorrect 8 ms 12032 KB Breaking single line is causing network to disconnect.
11 Halted 0 ms 0 KB -