#include <iostream>
#include <cstdio>
#include <vector>
#include <string>
#include <cmath>
#include <sstream>
#include <map>
#include <queue>
#include <stack>
#include <algorithm>
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)

using namespace std;

int main() {
	int L, N;
	string str;
	cin >> L >> N;

	int sum = 0;
	REP(i, N) {
		cin >> str;

		int n = L - str.length();
		sum += pow(2, n);
	}

	cout << sum << endl;

	return 0;
}