#include <bits/stdc++.h>    

using namespace std;

typedef long long ll;

const int N = (int)1e5 + 12, MOD = (int)1e9 + 7;

ll f[N], f1[N], p[N];
int n, m;
vector<vector<int>> cur;
ll binpow(ll a, ll b) {
    ll ret = 1, k = a;
    while(b) {
        if(b & 1) {
            ret *= k;
            ret %= MOD;
        }
        k *= k;
        k %= MOD;
        b /= 2;
    }
    return ret;
}
void prec() {
    p[0] = f1[0] = f[0] = 1;
    for(int i = 1; i <= n; i++) {
        f[i] = f[i - 1] * 1ll * i % MOD;
        f1[i] = binpow(f[i], MOD - 2);
        p[i] = p[i - 1] + f1[i];
        if(p[i] >= MOD) p[i] -= MOD;
    }
}
ll calc(ll s) {
    ll ret = f[s] * p[s] % MOD;
    return ret;
}
void test() {
    cin >> n >> m;
    prec();
    cur.resize(1);
    for(int i = 1; i <= n; i++) {
        cur[0].push_back(i);
    }
    for(int i = 0; i < m; i++) {
        string s;
        cin >> s;
        s = "~" + s;
        vector<vector<int>> nv;
        for(auto v:cur) {
            vector<int> e, h;
            for(int j:v) {
                if(s[j] == 'E') {
                    e.push_back(j);
                } else {
                    h.push_back(j);
                }
            }
            if(!e.empty()) {
                nv.push_back(e);
            }
            if(!h.empty()) {
                nv.push_back(h);
            }
        }
        nv.swap(cur);
    }
    ll res = 1;
    for(auto i:cur) {
        int s = (int)i.size();
        res *= calc(s);
        res %= MOD;

        // for(int j:i) {
        //     cout << j << ' ';
        // }
        // cout << '\n';
    }
    res--;
    if(res < 0) res += MOD;
    cout << res << '\n';
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int t = 1;
    // cin >> t;
    
    while(t--)
        test();
}