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  1. #include<bits/stdc++.h>
  2. using namespace std;
  3.  
  4. vector<vector<int> >g(20005);
  5. bool vis[20005];
  6.  
  7. int xx,yy,a,b,n,t;
  8.  
  9. void dfs(int source, bool p)
  10. {
  11.     if(vis[source]==true)
  12.     return;
  13.     vis[source]=true;
  14.     if(p)
  15.     xx++;
  16.     else
  17.     yy++;
  18.     int sz=g[source].size();
  19.     for(int i=0;i<sz;i++)
  20.     dfs(g[source][i],!p);
  21.     return;
  22. }
  23.  
  24. int main()
  25. {
  26.     cin>>t;
  27.     for(int i=1;i<=t;i++)
  28.     {
  29.         memset(vis,false,sizeof vis);
  30.         for(int j=0;j<=20004;j++)
  31.         g[j].clear();
  32.  
  33.         cin>>n;
  34.         for(int j=1;j<=n;j++)
  35.         {
  36.             scanf("%d%d",&a,&b);
  37.             g[a].push_back(b);
  38.             g[b].push_back(a);
  39.         }
  40.         int ans=0;
  41.         for(int j=1;j<=20003;j++)
  42.         if(vis[j]==false && g[j].size()>0)
  43.         {
  44.             xx=yy=0;
  45.             dfs(j,true);
  46.             ans+=max(xx,yy);
  47.         }
  48.         cout<<"Case "<<i<<": "<<ans<<endl;
  49.     }
  50.     return 0;
  51. }
  52.  
Success #stdin #stdout 0s 15264KB
comments (?)
stdin 
1
6
1 2
3 4
5 6
2 7
2 8
3 9
stdout 
Case 1: 6
https://ideone.com/eRdcIP
language:
C++ (gcc 8.3)
created:
7 years ago
visibility:
public

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