#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, mus[N], ban[N];
int cnt[M], lim[M];
int L[M], R[M];
int m, v[N], mask[M];
int now, cur = 1, dp[2][1 << N];
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]);
  }
  int least = 0;
  for(re int i = 0; i < M; ++i) {
    least += L[i]; if(L[i] > R[i]) {cout << 0; return 0;}
  }
  if(least > n) {cout << 0; return 0;}
  for(re int i = 0; i < M; ++i)
    for(re int j = 0; j < L[i]; ++j)
      mask[i] |= 1 << m, v[m++] = i;
  dp[0][0] = 1;
  for(re int i = 0; i < n; ++i) {
    swap(now, cur), memset(dp[now], 0, sizeof(now));
    for(re int S = 0; S < 1 << m; ++S) {
      int w = dp[cur][S];
      for(re int c = 0; c < m; ++c) {
        if(S >> c & 1) continue;
        if(c && v[c] == v[c - 1] && !(S >> (c - 1) & 1)) continue;
        if(~mus[i] && v[c] != mus[i]) continue;
        if(ban[i] >> v[c] & 1) continue;
        addr(dp[now][S | (1 << c)], w);
      }
      for(re int c = 0; c < M; ++c) {
        if((S & mask[c]) != mask[c]) continue;
        if(~mus[i] && c != mus[i]) continue;
        if((ban[i] >> c & 1) || R[c] <= n) continue;
        addr(dp[now][S], w);
      }
    }
  }
  cout << dp[now][(1 << m) - 1];
  cerr << 1.0 * clock() / CLOCKS_PER_SEC;
  return 0;
}