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#include <bits/stdc++.h>
using namespace std;

int n, m;
char board[10][10];
char res_board[10][10];
int strengths[10][10];
int parity[10][10];

int np_pawns;  // nieparzyste piony
int p_pawns;   // parzyste piony

int p_strength;
int np_strength;

int res_np_pawns;
int res_p_pawns;

int p;

void preprocess() {
  cin >> n >> m;

  for (int y = 0; y < 10; ++y) {
    for (int x = 0; x < 10; ++x) {
      board[y][x] = 'n';
      res_board[y][x] = 'n';
    }
  }

  for (int y = 1; y <= n; ++y)
    for (int x = 1; x <= m; ++x)
      cin >> board[y][x];

  for (int y = 1; y <= n; ++y)
    for (int x = 1; x <= m; ++x)
      cin >> res_board[y][x];

  p = 1;

  for (int y = 1; y <= n; ++y) {
    p = 1 - p;
    for (int x = 1; x <= m; ++x) {
      parity[y][x] = p;
      if (board[y][x] == 'O') {
        if (p == 1)
          p_pawns++;
        else
          np_pawns++;
      }
      p = 1 - p;
    }
  }

  p = 1;

  for (int y = 1; y <= n; ++y) {
    p = 1 - p;
    for (int x = 1; x <= m; ++x) {
      if (res_board[y][x] == 'O') {
        if (p == 1)
          res_p_pawns++;
        else
          res_np_pawns++;
      }
      p = 1 - p;
    }
  }

  for (int y = 1; y <= n; y++) {
    for (int x = 1; x <= m; x++) {
      int c = 0;
      if (board[y - 1][x] == 'O' || board[y - 1][x] == '.') c++;
      if (board[y + 1][x] == 'O' || board[y + 1][x] == '.') c++;
      if (board[y][x - 1] == 'O' || board[y][x - 1] == '.') c++;
      if (board[y][x + 1] == 'O' || board[y][x + 1] == '.') c++;
      strengths[y][x] = c;
    }
  }

  for (int y = 1; y <= n; y++) {
    for (int x = 1; x <= m; x++) {
      if (parity[y][x] == 1 && p_pawns == 0) strengths[y][x] = 0;
      if (parity[y][x] == 0 && np_pawns == 0) strengths[y][x] = 0;
      if (parity[y][x] == 1) p_strength += strengths[y][x];
      if (parity[y][x] == 0) np_strength += strengths[y][x];
    }
  }
}

void solve() {
  if (p_pawns != res_p_pawns || np_pawns != res_np_pawns) {
    cout << '0';
    return;
  }

  long double result = 1;
  for (int y = 1; y <= n; y++) {
    for (int x = 1; x <= m; x++) {
      if (res_board[y][x] == '.') continue;
      if (parity[y][x] == 1) {
        // parzyste
        long double w = ((long double)(strengths[y][x] * p_pawns)) / (long double)(p_strength);
        p_pawns--;
        result *= w;
      } else {
        // nieparzyste
        long double w = ((long double)(strengths[y][x] * np_pawns)) / (long double)(np_strength);
        np_pawns--;
        result *= w;
      }
    }
  }

  cout << fixed << setprecision(18) << result;
}

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

  preprocess();
  solve();

  return 0;
}