#include <bits/stdc++.h>
using namespace std;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  long long n, i, j, k, x, MOD = 1000000007, ans, a1, a2, b1, b2, a, b;
  string s1, s2;
  cin >> n >> s1 >> s2;
  vector<vector<long long>> dp(n + 1, vector<long long>(4, 0));
  dp[0][0] = 1;
  for (i = 0; i < n; i++) {
    for (j = 0; j < 4; j++) {
      if (s1[i] == '?')
        a1 = 0, a2 = 9;
      else
        a1 = s1[i] - '0', a2 = a1;
      if (s2[i] == '?')
        b1 = 0, b2 = 9;
      else
        b1 = s2[i] - '0', b2 = b1;
      for (a = a1; a <= a2; a++) {
        for (b = b1; b <= b2; b++) {
          x = j;
          if (a < b)
            x |= 1;
          else if (a > b)
            x |= 2;
          dp[i + 1][x] = (dp[i + 1][x] + dp[i][j]) % MOD;
        }
      }
    }
  }
  ans = dp[n][3];
  cout << ans << "\n";
  return 0;
}
