Light Oj 1009

#include <bits/stdc++.h>
using namespace std;
 
 
#define max1 100010
typedef map <int , int> mm;
typedef  vector <int> vc;
typedef long long int ll;
vc node[max1];
#define G -1
#define B 1
#define W 0
int x , y;
queue<int> mq;
mm  mp;
int grap_col[max1];
int maxi (int d , int p)
{
    if(d > p)
        return d;
    else
        return p;
}
void bfs_algo (int source)
{
 
    int u , v;
    grap_col[source] = B;
    mq.push(source);
 
    while(!mq.empty())
    {
        u =  mq.front();
        mq.pop();
 
 
        for(int i = 0; i < node[u].size(); i++)
        {
           v = node[u][i];
 
           if(grap_col[v] == G)
           {
               if(grap_col[u] == B)
               {
                   x++;
                   grap_col[v] = W;
               }
               else
               {
                   y++;
                   grap_col[v] = B;
               }
 
               mq.push(v);
           }
        }
    }
 
 
}
int main()
{
     int tes , o = 0;
 
     cin >> tes;
 
     while(tes--)
     {
         o++;
         int p , a ,b , in = 0;
         cin >> p;
         mp.clear();
 
         for(int i = 1; i <= p; i++)
         {
             cin>> a >> b;
             if(!mp[a])
             {
                 mp[a] = ++in;
                 node[mp[a]].clear();
             }
             if(!mp[b])
             {
                 mp[b] = ++in;
                 node[mp[b]].clear();
             }
             node[mp[a]].push_back(mp[b]);
             node[mp[b]].push_back(mp[a]);
         }
        memset(grap_col , G , sizeof grap_col);
        ll  sum = 0;
         for(int i =1; i <= in; i++)
         {
             if(grap_col[i] != G)
                continue;
             x = 0 ,y = 1;
             bfs_algo(i);
           sum = sum + maxi(x , y);
         }
 
 
      printf("Case %d: %lld\n",o , sum);
 
     }
 
}