#include <bits/stdc++.h>

using namespace std;

const int M = 102;
const int MX = 1e9 + 7;

namespace AC{
	const int A = 26;
	const int off = 'a';
	const int MAXN = 102;
	
	int V;
	bool finish[MAXN];

	int prv[MAXN];
	int fail[MAXN];
	int last[MAXN];
	int nxt[MAXN][A];
	
	void init(){
		V = 0;
		prv[0] = -1;
		fail[0] = 0;
	}
	
	void create(){
		++V;
		for(int i = 0; i < A; ++i)
			nxt[V][i] = 0;
		fail[V] = 0;
	}
	
	void add(string &s){
		int cur = 0;
		for(auto c: s){
			if(nxt[cur][c - off] == 0){
				create();
				prv[V] = cur;
				
				last[V] = c - off;
				nxt[cur][c - off] = V;
			}
			
			cur = nxt[cur][c - off];
		}
		
		finish[cur] = true;
	}
	
	void make(){
		for(int i = 1; i <= V; ++i){
			if(prv[i] == 0)
				fail[i] = 0;
			else
				fail[i] = nxt[fail[prv[i]]][last[i]];
			for(int j = 0; j < A; ++j)
				if(nxt[i][j] == 0)
					nxt[i][j] = nxt[fail[i]][j];
		}
	}
}

struct matrix{
	int t[M][M];
	matrix(bool id = false){
		for(int i = 0; i < M; ++i)
			for(int j = 0; j < M; ++j)
				t[i][j] = 0;
		
		if(id)
			for(int i = 0; i < M; ++i)
				t[i][i] = 1;
	}
};

matrix operator*(matrix a, matrix b){
	matrix ret;
	for(int i = 0; i < M; ++i)
		for(int j = 0; j < M; ++j)
			for(int k = 0; k < M; ++k)
				ret.t[i][j] = (ret.t[i][j] + 1LL * a.t[i][k] * b.t[k][j]) % MX;
	return ret;
}

int n, q;
matrix fast(matrix a, int b){
	matrix ret(true);
	while(b){
		if(b & 1)
			ret = ret * a;
		
		b >>= 1;
		a = a * a;
	}
	
	return ret;
}

int main(){
	cin >> n >> q;
	AC::init();

	for(int i = 1; i <= q; ++i){
		int xd;
		cin >> xd;
		string a;
		cin >> a;
		AC::add(a);
	}
	
	AC::make();
	matrix cur;
	for(int i = 0; i <= AC::V; ++i){
//		for(int j = 0; j < 26; ++j)
//			printf("%d ", AC::nxt[i][j]);
//		puts("");

		if(!AC::finish[i]){
			for(int j = 0; j < 26; ++j)
				cur.t[i][AC::nxt[i][j]]++;
		}
	}
	
	int ret = 0;
	matrix ans = fast(cur, n);
	for(int i = 0; i <= AC::V; ++i)
		if(!AC::finish[i])
			ret = (ret + ans.t[0][i]) % MX;
	cout << ret << "\n";
	return 0;
}