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#include <iostream>
#include <vector>
#include <random>
#include <iomanip>

#define PAWN 'O'
#define EMPTY '.'

#define DOWN 0
#define UP 1
#define LEFT 2
#define RIGHT 3

using namespace std;

void debug(const vector<vector<char>> &v) {
	for (int i = 0; i < v.size(); ++i) {
		for (int j = 0; j < v[0].size(); ++j) {
			cout << v[i][j];
		}
		cout << '\n';
	}

	cout << '\n';
}

mt19937 rng(2137);
int random_range(int l, int r) {
	return uniform_int_distribution<int>(l, r)(rng);
}

int random_element(const vector<int> &v) {
	return v[random_range(0, v.size() - 1)];
}

bool can_move(const pair<int, int> &pawn, const vector<vector<char>> &pos, int n, int m) {
	int i = pawn.first;
	int j = pawn.second;

	return (i + 1 < n && pos[i + 1][j] == EMPTY)
		|| (i - 1 >= 0 && pos[i - 1][j] == EMPTY)
		|| (j + 1 < m && pos[i][j + 1] == EMPTY)
		|| (j - 1 >= 0 && pos[i][j - 1] == EMPTY);
}

vector<int> pawn_directions(const pair<int, int> &pawn, const vector<vector<char>> &pos, int n, int m) {
	int i = pawn.first;
	int j = pawn.second;
	vector<int> ret;
	if (i + 1 < n && pos[i + 1][j] == EMPTY) {
		ret.push_back(DOWN);
	}
	if (i - 1 >= 0 && pos[i - 1][j] == EMPTY) {
		ret.push_back(UP);
	}
	if (j - 1 >= 0 && pos[i][j - 1] == EMPTY) {
		ret.push_back(LEFT);
	}
	if (j + 1 < m && pos[i][j + 1] == EMPTY) {
		ret.push_back(RIGHT);
	}

	return ret;
}

void make_move2(const pair<pair<int, int>, pair<int, int>> &move, vector<vector<char>> &init_pos, vector<pair<int, int>> &pawns) {
	swap(init_pos[move.first.first][move.first.second], init_pos[move.second.first][move.second.second]);

	int pawn_index_in_pawns = -1;
	for (int k = 0; k < pawns.size(); ++k) {
		if (pawns[k].first == move.first.first && pawns[k].second == move.first.second) {
			pawn_index_in_pawns = k;
			break;
		}
	}

	pawns[pawn_index_in_pawns] = move.second;
}

void make_move(const pair<int, int> &pawn, int direction, vector<vector<char>> &init_pos, vector<pair<int, int>> &pawns) {
	int i = pawn.first;
	int j = pawn.second;
	int pawn_index_in_pawns = -1;
	for (int k = 0; k < pawns.size(); ++k) {
		if (pawns[k].first == i && pawns[k].second == j) {
			pawn_index_in_pawns = k;
			break;
		}
	}

	pair<int, int> new_pawn_index = {i, j};
	switch (direction) {
		case DOWN:
			++new_pawn_index.first;
			break;
		case UP:
			--new_pawn_index.first;
			break;
		case LEFT:
			--new_pawn_index.second;
			break;
		case RIGHT:
			++new_pawn_index.second;
			break;
	}

	pawns[pawn_index_in_pawns] = new_pawn_index;
	swap(init_pos[i][j], init_pos[new_pawn_index.first][new_pawn_index.second]);
}
	

long double solve(vector<vector<char>> init_pos, const vector<vector<char>> &end_pos) {
	int n = init_pos.size();
	int m = init_pos[0].size();
	vector<pair<int, int>> pawns;
	for (int i = 0; i < init_pos.size(); ++i) {
		for (int j = 0; j < init_pos[0].size(); ++j) {
			if (init_pos[i][j] == PAWN) {
				pawns.push_back({i, j});
			}
		}
	}


	const int simulation_cnt = 1e6;
	int end_pos_cnt = 0;
	for (int i = 0; i < simulation_cnt; ++i) {
		/*
		vector<pair<int, int>> pawns_can_move;
		for (auto pawn : pawns) {
			if (can_move(pawn, init_pos, n, m)) {
				pawns_can_move.push_back(pawn);
			}
		}
		pair<int, int> pawn = pawns_can_move[random_range(0, pawns.size() - 1)];
		vector<int> directions = pawn_directions(pawn, init_pos, n, m);
		int direction = random_element(directions);

		make_move(pawn, direction, init_pos, pawns);
		*/

		vector<pair<pair<int, int>, pair<int, int>>> moves;
		for (const auto &pawn : pawns) {
			vector<int> directions = pawn_directions(pawn, init_pos, n, m);
			for (const int &direction : directions) {
				switch (direction) {
					case UP:
						moves.push_back({pawn, {pawn.first - 1, pawn.second}});
						break;
					case DOWN:
						moves.push_back({pawn, {pawn.first + 1, pawn.second}});
						break;
					case LEFT:
						moves.push_back({pawn, {pawn.first, pawn.second - 1}});
						break;
					case RIGHT:
						moves.push_back({pawn, {pawn.first, pawn.second + 1}});
						break;
				}
			}
		}

		int move_numb = random_range(0, moves.size() - 1);
		make_move2(moves[move_numb], init_pos, pawns);
		

		// debug(init_pos);
		// debug(end_pos);

		if (i % 2 != 0) {
			// debug(init_pos);
			bool equal = true;
			for (int k = 0; k < n; ++k) {
				for (int l = 0; l < m; ++l) {
					if (init_pos[k][l] != end_pos[k][l]) {
						equal = false;
						break;
					}
				}
			}

			if (equal) {
				++end_pos_cnt;
			}
		}
	}


	cout << end_pos_cnt << '\n';
	cout << simulation_cnt << '\n';
	return (long double)end_pos_cnt*2/simulation_cnt;
}

long double solve2(vector<vector<char>> init_pos, const vector<vector<char>> &end_pos) {
	int n = init_pos.size();
	int m = init_pos[0].size();

	const int simulation_cnt = 1e5;
	int end_pos_cnt = 0;
	for (int i = 0; i < simulation_cnt; ++i) {
		if (i % 2 == 0) {
			bool equal = true;
			for (int j = 0; j < n; ++j) {
				for (int k = 0; k < m; ++k) {
					if (init_pos[j][k] != end_pos[j][k]) {
						equal = false;
						break;
					}
				}
			}

			if (equal) {
				++end_pos_cnt;
			}
		}

		vector<pair<pair<int, int>, pair<int, int>>> moves;
		for (int j = 0; j < n; ++j) {
			for (int k = 0; k < m; ++k) {
				if (init_pos[j][k] == EMPTY) {
					continue;
				}


				if (j + 1 < n && init_pos[j + 1][k] == EMPTY) {
					moves.push_back({{j, k}, {j + 1, k}});
				}
				if (j - 1 >= 0 && init_pos[j - 1][k] == EMPTY) {
					moves.push_back({{j, k}, {j - 1, k}});
				}
				if (k + 1 < m && init_pos[j][k + 1] == EMPTY) {
					moves.push_back({{j, k}, {j, k + 1}});
				}
				if (k - 1 >= 0 && init_pos[j][k - 1] == EMPTY) {
					moves.push_back({{j, k}, {j, k - 1}});
				}
			}
		}

		int move_numb = random_range(0, moves.size() - 1);
		auto move = moves[move_numb];
		swap(init_pos[move.first.first][move.first.second], init_pos[move.second.first][move.second.second]);


	}

	return (long double)end_pos_cnt * 2.0 / (long double)simulation_cnt;
}

int main() {
	int n, m;
	cin >> n >> m;
	vector<vector<char>> init_pos(n, vector<char>(m));
	for (auto &row : init_pos) {
		for (char &entry : row) {
			cin >> entry;
		}
	}
	string empty_line;
	getline(cin, empty_line);

	vector<vector<char>> end_pos(n, vector<char>(m));
	for (auto &row : end_pos) {
		for (char &entry : row) {
			cin >> entry;
		}
	}

	long double answer = solve2(init_pos, end_pos);

	cout << fixed << setprecision(15) << answer << endl;

	return 0;
}