#include <bits/stdc++.h>
using namespace std;
///
ifstream fin("lant2.in");
ofstream fout("lant2.out");
const short Cuvmax=35;
const short Nrdist=160;
const int Pmax=1005;

char s[Pmax], a[Nrdist][Cuvmax], *p, sep[]=" ,:;.!?-";
int k,n, grad[Nrdist],gradcpy[Nrdist], S[Nrdist];
vector<short> L[Nrdist+105];
queue<int> Q;
void Citire()
{
    fin>>k;fin.get();
    n=0;
    while(fin.getline(s,Pmax))
    {
        p=strtok(s,sep);
        while(p)
        {
          bool ok=false;
          for(int i=1;i<=n && !ok; ++i)
            if(strcmp(p,a[i])==0) ok=true;
          if(!ok)
          {
              ++n;
              strcpy(a[n],p);
          }
          p=strtok(0,sep);
        }
    }
}
int Levenshtein(char b[], char c[])
{
    int dp[Cuvmax][Cuvmax],X, Y;
    X=strlen(b);Y=strlen(c);
    ///initializari
    for(int i=0;i<=X;i++)dp[i][0]=i;
    for(int i=0;i<=Y;i++)dp[0][i]=i;

    for(int i=0;i<X;i++)
        for(int j=0;j<Y;j++)
    {
        dp[i+1][j+1]=min(1+dp[i][j+1], 1+dp[i+1][j]);
        if(b[i]==c[j] && dp[i+1][j+1]>dp[i][j]) dp[i+1][j+1]=dp[i][j];
    }
    return dp[X][Y];
}
void Solutie()
{
    for(int i=1;i<n;i++)
        for(int j=i+1;j<=n;j++)
          if(Levenshtein(a[i], a[j])<=k)
    {
        ++grad[j];
        ++gradcpy[i];
        L[i].push_back(j);
    }
    ///bfs
    S[1]=1;
    for(int i=1;i<=n;i++)
        if(!grad[i])Q.push(i);
    while(!Q.empty())
    {
        int varf=Q.front();
        Q.pop();
        for(unsigned int j=0;j<L[varf].size();j++)
        {
            int w=L[varf][j];
            S[w]+=S[varf];
            --grad[w];
            if(!grad[w]) Q.push(w);
        }
    }
    ///numarare sol
    long long sol=0;
    for(int i=1;i<=n;i++)
        if(!gradcpy[i])
         sol+=S[i];
    fout<<sol;

}
int main()
{
  Citire();
  Solutie();
  return 0;
}