#include <bits/stdc++.h>
#define il inline
#define re register
#define ll long long
#define ull unsigned ll
#define pii pair<int, int>
#define fi first
#define se second
#define eb emplace_back
using namespace std;
#define N 19
#define M 26
#define P 1000000007
il void addr(int &x, int y) {(x += y) >= P && (x -= P);}
int n, m, mus[N], ban[N];
int cnt[M], lim[M];
int L[M], R[M];
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0), cout.tie(0);
  int T; cin >> T >> n;
  memset(mus, -1, sizeof(mus));
  memset(R, 0x3f, sizeof(R));
  while(T--) {
    string A, B; cin >> A >> B;
    memset(cnt, 0, sizeof(cnt));
    memset(lim, 0x3f, sizeof(lim));
    for(re int i = 0; i < n; ++i) {
      int c = A[i] - 'A', v = B[i];
      if(v == 'x') lim[c] = cnt[c], ban[i] |= 1 << c;
      if(v == '-') ++cnt[c], ban[i] |= 1 << c;
      if(v == 'O') mus[i] = c, ++cnt[c];
    }
    for(re int i = 0; i < M; ++i)
      L[i] = max(L[i], cnt[i]), R[i] = min(R[i], lim[i]);
  }
  // for(re int i = 0; i < M; ++i)
  //   cout << char(i + 'A') << " = " << L[i] << ", " << R[i] << "\n";
  // for(re int i = 0; i < n; ++i)
  //   if(~mus[i]) cout << i << " must = " << char(mus[i] + 'A') << "\n";
  map<vector<int>, int> dp;
  dp[vector<int>(M, 0)] = 1;
  for(re int i = 0; i < n; ++i) {
    map<vector<int>, int> ndp; swap(dp, ndp);
    for(auto it : ndp) {
      auto v = it.fi; int w = it.se, need = 0;
      for(re int c = 0; c < M; ++c) need += L[c] - v[c];
      for(re int c = 0; c < M; ++c) {
        if(~mus[i] && c != mus[i]) continue;
        if(v[c] == R[c]) continue;
        if(ban[i] >> c & 1) continue;
        // cout << "trans " << i << " " << char(c + 'A') << "\n";
        int las = v[c], nxt = v[c] + 1;
        if(R[c] > n) nxt = min(nxt, L[c]);
        if(need - (L[c] - las) + (L[c] - nxt) >= n - i) continue;
        v[c] = nxt, addr(dp[v], w), v[c] = las;
      }
    }
  }
  int ans = 0;
  for(auto it : dp) {
    auto v = it.fi; int w = it.se; bool F = 1;
    for(re int c = 0; c < M; ++c) {
      if(v[c] < L[c]) F = 0;
      if(R[c] <= n && v[c] < R[c]) F = 0;
    }
    if(F) addr(ans, w);
  }
  cout << ans;
  cerr << 1.0 * clock() / CLOCKS_PER_SEC;
  return 0;
}