#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],S[Nrdist],gradcpy[Nrdist];
vector<short>L[Nrdist+105];
queue<int>Q;
inline void Read()
{
    fin>>k;
    fin.get();
    n=0;
    while (fin.getline(s,1001))
    {
        p=strtok(s,sep);
        ///separam textul de ,:;.!? etc
        while (p!=NULL)
        {
            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(NULL,sep);
        }
    }
}
inline int Levenshtein(const char b[],const char c[])
{
    ///dp[i][j]-numarul minim de operatii de a transforma primele  i caractere din b[i]
    ///         in primele j caractere din c[i]
    int X,Y,dp[Cuvmax][Cuvmax];
    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])///move
                dp[i+1][j+1]=dp[i][j];
        }
    return dp[X][Y];
}
inline void Solve()
{
    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);
            }
    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++)         ///aflu numarul de lanturi de la nodul 1 la nodul i
        {
            int w=L[varf][j];
            S[w]+=S[varf];
            --grad[w];
            if(!grad[w])
                Q.push(w);
        }
    }
    long long sol=0;
    for(int i=1; i<=n; i++)
        if(!gradcpy[i])
            sol+=S[i];  ///in varful i se opreste lantul(varful nu mai are adiacenti)
    fout<<sol<<"\n";
}
int main()
{
    Read();
    Solve();
    fin.close();
    fout.close();
    return 0;
}