#include <algorithm>
#include <cstdio>
#include <iostream>
#include <map>
#include <cmath>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <vector>
#include <stdlib.h>
#include <stdio.h>
#include <bitset>
using namespace std;
#define FOR(I,A,B) for(int I = (A); I < (B); ++I)
typedef long long ll;

int main(){
  int L,N;
  cin>>L>>N;
  vector<string> vs(N);
  FOR(i,0,N) cin>>vs[i];
  ll ans = 0;
  FOR(i,0,N){
    ans += pow(2,L-vs[i].length());
  }
  cout << ans << endl;
  return 0;
}