#include <bits/stdc++.h>

using namespace std;
ifstream in("nrcuv.in");
ofstream out("nrcuv.out");
int n,m,v[30][30],dp[1100],p1,p2;
char c1,c2;
int main()
{
    in>>n>>m;
    dp[1]=26;
    for(int i=1;i<=m;i++)
    {
        in>>c1>>c2;
        if(v[c1-'a'+1][c2-'a'+1]==0) {
            if(c1==c2) p1++;
            else p2++;
        }
        v[c1-'a'+1][c2-'a'+1]=1;
        v[c2-'a'+1][c1-'a'+1]=1;
    }
    for(int i=2;i<=n;i++)
        dp[i]=26*dp[i-1]-2*p2-p1+26*dp[i-2];
    out<<dp[n];
    return 0;
}