#include<stdio.h>
//#include<bits/stdc++.h>
#include<string.h>
#include<iostream>
#include<math.h>
#include<sstream>
#include<set>
#include<queue>
#include<map>
#include<vector>
#include<algorithm>
#include<limits.h>
#define inf 0x3fffffff
#define INF 0x3f3f3f3f
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
#define LL long long
#define ULL unsigned long long
using namespace std;
int n;
string ss[100];
set<string> q;
int main ()
{
    while(cin>>n)
    {
        int i,j;
        for(i=0; i<n; i++)
        {
            cin>>ss[i];
        }
        for(i=0; i<n; i++)
        {
            for(j=0; j<n; j++)
            {
                int sum=0;
                if(i==j) continue;
                if(ss[i].length()==ss[j].length())
                {
                    for(int z=0; z<ss[i].length(); z++)
                    {
                        if(ss[i][z]==ss[j][z]||abs(ss[i][z]-ss[j][z])==32)
                        {
                            sum++;
                        }
                    }
                    if(sum>2)
                    {
                  //      cout<<ss[i]<<" "<<ss[j]<<endl;
                        q.insert(ss[j]);
                    }
                }

            }
        }
        cout<<q.size()<<endl;
        q.clear();
    }
    return 0;
}