#include <bits/stdc++.h>
using namespace std;

signed main(){
  int L, N; cin >> L >> N;
  int ans = 0;
  for( int i = 0; i < N; ++i ){
    string S; cin >> S;
    if( L < S.size() ) continue;
    ans += 1 << ( L - S.size() );
  }
  cout << ans << endl;
  return 0;
}