#include <iostream>
#include <fstream>
#define MAX 2000
using namespace std;

typedef struct {
char sursa, destin;
} excep;

int main()
{
    ifstream in("nrcuv.in");
    ofstream out("nrcuv.out");

    long long litere, nr,i,j;
    excep arr[MAX];
    in >> litere >>nr;
    long long diferite = 0,egal = 0;
    for(i = 0 ; i != nr; i++){
        in >> arr[i].sursa >> arr[i].destin;
        long long aux = 0;
        for (j = 0; j != i; j++){
            if((arr[i].sursa == arr[j].sursa && arr[i].destin == arr[j].destin)
            || (arr[i].sursa == arr[j].destin && arr[i].destin == arr[j].sursa)) aux = 1;
        }
        if(aux == 0) {
             if(arr[i].sursa != arr[i].destin)diferite++;
             else egal++;
        }
    }
    long long res = 26;
    for(i = 1; i < litere; i++){
        res *=26;
        res -= (diferite * (i+1));
        res -= (egal * i );
    }
    out << res<<endl;
    return 0;
}