# |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
638409 |
2022-09-05T21:05:52 Z |
xad |
Network (BOI15_net) |
C++17 |
|
1 ms |
336 KB |
#include <bits/stdc++.h>
using namespace std ;
#define nn "\n"
#define x_x ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define intt int t; cin>>t; while(t--)
#define emp emplace_back
#define mod 1000000007
#define all(v) v.begin(), v.end()
#define sz(x) (int)x.size()
//#define a first
//#define b second
typedef long long ll;
int main()
{
x_x
int n; cin>>n; vector<int>adj[n+2]; vector<pair<int,int>>v,ch; int p[n+2];
for(int i=1,x,y; i<n; i++)cin>>x>>y, adj[x].emp(y), adj[y].emp(x),p[x]=y,p[y]=x;
for(int i=1; i<=n; i++)
if(sz(adj[i])==1)
{
ch.push_back({p[i],i});
}
sort(all(ch));
vector<int>df;
for(int i=0; i<sz(ch)-1; i++)
{
if(ch[i].first!=ch[i+1].first)
{
if(!df.empty()&&df.back()==ch[i].second)df.pop_back();
df.emp(ch[i].second), df.emp(ch[i+1].second);
ch[i].first=0;
if(i==(sz(ch)-2))ch[i+1].first=0;
}
else if(!df.empty()&&df.back()==ch[i].second)ch[i].first=0;
}
for(int i=0; i<sz(df)-1; i+=2)v.push_back({df[i],df[i+1]});
if(sz(df)%2)//v.push_back({df[0],df.back()});
{
for(auto&i:ch)
{
if(i.second==df.back()){i.first=1; break;}
}
}
int c=0;
for(int i=0,j=0; i<sz(ch); i++)
{
if(!ch[i].first)continue;
while(c!=-1&&(!ch[j].first||i==j))
{ if(c==sz(ch)){c=-1; break;} j=(j+1)%sz(ch); ++c;}
if(c==-1)
{if(i==j)j=(j+1)%sz(ch); }
else c=0;
v.push_back({ch[i].second,ch[j].second}), ch[j].first=0;
ch[i].first=0;
}
cout<<sz(v)<<nn;
for(auto i:v)cout<<i.first<< ' '<<i.second<<nn;
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
336 KB |
Output is correct |
2 |
Correct |
0 ms |
212 KB |
Output is correct |
3 |
Correct |
0 ms |
212 KB |
Output is correct |
4 |
Correct |
0 ms |
212 KB |
Output is correct |
5 |
Correct |
1 ms |
212 KB |
Output is correct |
6 |
Correct |
0 ms |
212 KB |
Output is correct |
7 |
Correct |
0 ms |
212 KB |
Output is correct |
8 |
Correct |
1 ms |
212 KB |
Output is correct |
9 |
Correct |
0 ms |
212 KB |
Output is correct |
10 |
Correct |
0 ms |
212 KB |
Output is correct |
11 |
Correct |
0 ms |
212 KB |
Output is correct |
12 |
Correct |
0 ms |
212 KB |
Output is correct |
13 |
Correct |
0 ms |
324 KB |
Output is correct |
14 |
Correct |
0 ms |
320 KB |
Output is correct |
15 |
Incorrect |
1 ms |
320 KB |
Breaking single line is causing network to disconnect. |
16 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
336 KB |
Output is correct |
2 |
Correct |
0 ms |
212 KB |
Output is correct |
3 |
Correct |
0 ms |
212 KB |
Output is correct |
4 |
Correct |
0 ms |
212 KB |
Output is correct |
5 |
Correct |
1 ms |
212 KB |
Output is correct |
6 |
Correct |
0 ms |
212 KB |
Output is correct |
7 |
Correct |
0 ms |
212 KB |
Output is correct |
8 |
Correct |
1 ms |
212 KB |
Output is correct |
9 |
Correct |
0 ms |
212 KB |
Output is correct |
10 |
Correct |
0 ms |
212 KB |
Output is correct |
11 |
Correct |
0 ms |
212 KB |
Output is correct |
12 |
Correct |
0 ms |
212 KB |
Output is correct |
13 |
Correct |
0 ms |
324 KB |
Output is correct |
14 |
Correct |
0 ms |
320 KB |
Output is correct |
15 |
Incorrect |
1 ms |
320 KB |
Breaking single line is causing network to disconnect. |
16 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
336 KB |
Output is correct |
2 |
Correct |
0 ms |
212 KB |
Output is correct |
3 |
Correct |
0 ms |
212 KB |
Output is correct |
4 |
Correct |
0 ms |
212 KB |
Output is correct |
5 |
Correct |
1 ms |
212 KB |
Output is correct |
6 |
Correct |
0 ms |
212 KB |
Output is correct |
7 |
Correct |
0 ms |
212 KB |
Output is correct |
8 |
Correct |
1 ms |
212 KB |
Output is correct |
9 |
Correct |
0 ms |
212 KB |
Output is correct |
10 |
Correct |
0 ms |
212 KB |
Output is correct |
11 |
Correct |
0 ms |
212 KB |
Output is correct |
12 |
Correct |
0 ms |
212 KB |
Output is correct |
13 |
Correct |
0 ms |
324 KB |
Output is correct |
14 |
Correct |
0 ms |
320 KB |
Output is correct |
15 |
Incorrect |
1 ms |
320 KB |
Breaking single line is causing network to disconnect. |
16 |
Halted |
0 ms |
0 KB |
- |