# |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
51138 |
2018-06-16T12:22:35 Z |
faustaadp |
Network (BOI15_net) |
C++17 |
|
12 ms |
12264 KB |
#include<bits/stdc++.h>
#define ll long long
#define pb push_back
#define mp make_pair
#define fi first
#define se second
using namespace std;
ll n,ta,tb,i,dg[505050],Vs,R;
vector<ll> v[505050],V;
void dfs(ll aa,ll bb)
{
//cout<<aa<<" "<<bb
if(dg[aa]==1)
V.pb(aa);
ll ii;
for(ii=0;ii<v[aa].size();ii++)
if(v[aa][ii]!=bb)
dfs(v[aa][ii],aa);
}
int main()
{
cin>>n;
for(i=1;i<n;i++)
{
cin>>ta>>tb;
v[ta].pb(tb);
v[tb].pb(ta);
dg[ta]++;
dg[tb]++;
}
for(i=1;i<=n;i++)
if(dg[i]>1)
R=i;
dfs(R,-1);
Vs=V.size();
if(Vs%2==1)
{
V.pb(V[Vs-1]);
Vs++;
}
cout<<Vs/2<<"\n";
for(i=0;i<Vs/2;i++)
cout<<V[i]<<" "<<V[Vs-i-1]<<"\n";
}
Compilation message
net.cpp: In function 'void dfs(long long int, long long int)':
net.cpp:16:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(ii=0;ii<v[aa].size();ii++)
~~^~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
12 ms |
12152 KB |
Output is correct |
2 |
Incorrect |
11 ms |
12264 KB |
Breaking single line is causing network to disconnect. |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
12 ms |
12152 KB |
Output is correct |
2 |
Incorrect |
11 ms |
12264 KB |
Breaking single line is causing network to disconnect. |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
12 ms |
12152 KB |
Output is correct |
2 |
Incorrect |
11 ms |
12264 KB |
Breaking single line is causing network to disconnect. |
3 |
Halted |
0 ms |
0 KB |
- |