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#include<bits/stdc++.h>
using namespace std;
using LL=long long;
#define FOR(i,l,r) for(int i=(l);i<=(r);++i)
#define REP(i,n) FOR(i,0,(n)-1)
#define ssize(x) int(x.size())
template<class A,class B>auto&operator<<(ostream&o,pair<A,B>p){return o<<'('<<p.first<<", "<<p.second<<')';}
template<class T>auto operator<<(ostream&o,T x)->decltype(x.end(),o){o<<'{';int i=0;for(auto e:x)o<<(", ")+2*!i++<<e;return o<<'}';}
#ifdef DEBUG
#define debug(x...) cerr<<"["#x"]: ",[](auto...$){((cerr<<$<<"; "),...)<<'\n';}(x)
#else
#define debug(...) {}
#endif

struct frac {
	LL nom, den;
	frac() {
		nom = 0;
		den = 1;
	}
	frac(LL a, LL b) : nom(a), den(b) {}
	friend bool operator<(frac p, frac q) {
		return p.nom * q.den < q.nom * p.den;
	}
	friend frac operator+(frac p, frac q) {
		frac ret(p.nom * q.den + q.nom * p.den, p.den * q.den);
		LL g = __gcd(ret.nom, ret.den);
		return frac(ret.nom / g, ret.den / g);
	}
	friend frac operator-(frac p, frac q) {
		frac ret(p.nom * q.den - q.nom * p.den, p.den * q.den);
		LL g = __gcd(ret.nom, ret.den);
		return frac(ret.nom / g, ret.den / g);
	}
	friend frac operator*(frac p, frac q) {
		p.nom *= q.nom;
		p.den *= q.den;
		LL g = __gcd(p.nom, p.den);
		return frac(p.nom / g, p.den / g);
	}
	friend frac operator/(frac p, frac q) {
		swap(q.nom, q.den);
		return p * q;
	}
};

int main() {
	cin.tie(0)->sync_with_stdio(0);
	int n, m;
	cin >> n >> m;
	vector t(n, vector (m, 'a'));
	REP (i, n)
		REP (j, m)
			cin >> t[i][j];

	auto solve = [&](vector<vector<char>> p) {
		vector cur(n, vector (m, frac(1, 1)));
		vector odw(n, vector (m, 0));
		vector zli(5, vector<pair<int, int>>());
		int licz = 0;

		auto good = [&](int x, int y) {
			if (x < 0 || y < 0 || n <= x || m <= y)
				return false;
			return p[x][y] == 'O';
		};

		function<void(int, int)> dfs = [&](int x, int y) {
			odw[x][y] = licz;
			int deg = 0;
			if (good(x - 1, y)) {
				++deg;
				if (odw[x - 1][y] < licz)
					dfs(x - 1, y);
			}
			if (good(x + 1, y)) {
				++deg;
				if (odw[x + 1][y] < licz)
					dfs(x + 1, y);
			}
			if (good(x, y - 1)) {
				++deg;
				if (odw[x][y - 1] < licz)
					dfs(x, y - 1);
			}
			if (good(x, y + 1)) {
				++deg;
				if (odw[x][y + 1] < licz)
					dfs(x, y + 1);
			}
			zli[deg].emplace_back(x, y);
		};

		bool ok = true;
		while (ok) {
			ok = false;
			++licz;
			REP (i, n) {
				REP (j, m) {
					if (odw[i][j] < licz && p[i][j] == 'O') {
						REP (k, 5)
							zli[k].clear();
						dfs(i, j);
						if (ssize(zli[0]))
							continue;
						ok = true;
						frac score(100, 0);
						FOR (k, 1, 4) {
							for (auto [a, b] : zli[k]) {
								score = min(score, cur[a][b] / frac(k, 1));
							}
						}
						FOR (k, 1, 4) {
							for (auto [a, b] : zli[k]) {
								cur[a][b] = cur[a][b] - frac(k, 1) * score;
								if (cur[a][b].nom == 0)
									p[a][b] = '.';
							}
						}
					}
				}
			}
		}
		frac sum;
		REP (i, n)
			REP (j, m)
				if (p[i][j] == 'O')
					sum = sum + cur[i][j];
		return sum;
	};

	vector<pair<int, int>> znaki;
	REP (i, n) {
		REP (j, m) {
			if (t[i][j] == '?')
				znaki.emplace_back(i, j);
		}
	}

	frac odp;
	int M = ssize(znaki);
	REP (mask, 1 << M) {
		REP (i, M) {
			if ((mask >> i) & 1)
				t[znaki[i].first][znaki[i].second] = 'O';
			else
				t[znaki[i].first][znaki[i].second] = '.';
		}
		auto ans = solve(t);
		odp = odp + ans;
	}

	odp = odp / frac(1 << M, 1);

	cout << odp.nom << '/' << odp.den << endl;
}