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#include <bits/stdc++.h>
#ifdef LOC
#include "debuglib.h"
#else
#define deb(...)
#define DBP(...)
#endif
using namespace std;
using   ll         = long long;
using   vi         = vector<int>;
using   pii        = pair<int, int>;
#define pb           push_back
#define mp           make_pair
#define x            first
#define y            second
#define rep(i, b, e) for (int i = (b); i < (e); i++)
#define each(a, x)   for (auto& a : (x))
#define all(x)       (x).begin(), (x).end()
#define sz(x)        int((x).size())

ll gcd(ll a, ll b) {
	while (b) a %= b, swap(a, b);
	return a;
}

struct frac {
	ll a, b;

	frac(ll x = 0) : a(x), b(1) {}

	frac(ll x, ll y) : a(x), b(y) {
		if (y < 0) a *= -1, b *= -1;
		reduce();
	}

	void reduce() {
		ll g = gcd(abs(a), b);
		a /= g;
		b /= g;
	}

	frac operator+(frac r) const { return {a*r.b + r.a*b, b*r.b}; }
	frac operator-(frac r) const { return {a*r.b - r.a*b, b*r.b}; }
	frac operator*(frac r) const { return {a*r.a, b*r.b}; }
	frac operator/(frac r) const { return {a*r.b, b*r.a}; }

	frac& operator+=(frac r) { return *this = *this + r; }
	frac& operator-=(frac r) { return *this = *this - r; }
	frac& operator*=(frac r) { return *this = *this * r; }
	frac& operator/=(frac r) { return *this = *this / r; }

	bool operator==(frac r) const { return a == r.a && b == r.b; }
	bool operator!=(frac r) const { return a != r.a || b != r.b; }
	bool operator<(frac r) const { return a*r.b < b*r.a; }
	bool operator>(frac r) const { return a*r.b > b*r.a; }
	bool operator<=(frac r) const { return a*r.b <= b*r.a; }
	bool operator>=(frac r) const { return a*r.b >= b*r.a; }
};

ostream& operator<<(ostream& out, frac f) {
	return out << f.a << '/' << f.b;
}

// ---

int n, m;
vector<string> mat;
vector<vector<frac>> rem;
vector<vi> seen;

frac solveDecided(pii start, int depth) {
	if (rem[start.x][start.y].a == 0) return 0;
	if (seen[start.x][start.y] >= depth) return 0;
	seen[start.x][start.y] = depth;

	vector<pii> comp = {start};
	vi deg;
	frac sub = 1;

	auto check = [&](int i, int j) {
		if (i < 0 || j < 0 || i >= n || j >= m) return 0;
		if (rem[i][j].a == 0) return 0;
		if (seen[i][j] < depth) {
			seen[i][j] = depth;
			comp.pb({i, j});
		}
		return 1;
	};

	rep(i, 0, sz(comp)) {
		pii v = comp[i];
		int k = check(v.x-1, v.y);
		k += check(v.x+1, v.y);
		k += check(v.x, v.y-1);
		k += check(v.x, v.y+1);
		deg.pb(k);
		sub = min(sub, rem[v.x][v.y] / k);
	}

	if (sz(comp) <= 1) {
		return rem[start.x][start.y];
	}

	rep(i, 0, sz(comp)) {
		pii v = comp[i];
		rem[v.x][v.y] -= sub * deg[i];
	}

	frac ret = 0;
	rep(i, 0, sz(comp)) {
		ret += solveDecided(comp[i], depth+1);
	}
	return ret;
}

frac solveDecided() {
	frac ret = 0;
	seen.assign(n, vi(m, 0));
	rep(i, 0, n) rep(j, 0, m) {
		ret += solveDecided({i, j}, 1);
	}
	return ret;
}

frac solveExp() {
	int undecided = 0;
	each(row, mat) undecided += int(count(all(row), '?'));

	frac ans = 0;
	rem.assign(n, vector<frac>(m, 0));

	rep(mask, 0, 1<<undecided) {
		int rest = mask;
		rep(i, 0, n) {
			rep(j, 0, m) {
				if (mat[i][j] == '?') {
					rem[i][j] = (rest & 1);
					rest >>= 1;
				} else {
					rem[i][j] = (mat[i][j] == 'O');
				}
			}
		}
		ans += solveDecided();
	}

	ans /= 1 << undecided;
	return ans;
}

// ---

frac pieces[1<<16];

void precompPieces() {
	int savedN = n, savedM = m;
	n = m = 4;
	rem.assign(4, vector<frac>(4));
	rep(mask, 0, 1<<16) {
		rep(i, 0, 16) {
			rem[i/4][i%4] = (mask >> i) & 1;
		}
		pieces[mask] = solveDecided();
	}
	n = savedN;
	m = savedM;
}

frac solvePiece(int i, int j) {
	int decided = 0;
	int undecided = 0;
	frac ret = 0;

	rep(a, 0, 4) rep(b, 0, 4) {
		if (i+a < n && j+b < m) {
			char chr = mat[i+a][j+b];
			int bit = a*4+b;
			if (chr == 'O') decided |= 1 << bit;
			else if (chr == '?') undecided |= 1 << bit;
		}
	}

	for (int part = undecided;; part = (part-1) & undecided) {
		ret += pieces[decided | part];
		if (!part) break;
	}
	return ret / (1 << __builtin_popcount(undecided));
}

frac solvePiecewise() {
	frac ret = 0;
	precompPieces();
	for (int i = 0; i < n; i += 5) {
		for (int j = 0; j < m; j += 5) {
			ret += solvePiece(i, j);
		}
	}
	return ret;
}

// ---

frac prob1(int i, int j) {
	if (i < 0 || j < 0 || i >= n || j >= m) return 0;
	return mat[i][j] == 'O' ? frac(1) : mat[i][j] == '.' ? frac(0) : frac(1, 2);
}

frac prob0(int i, int j) {
	return frac(1) - prob1(i, j);
}

frac patternAt(int offset, const vector<vi>& pat) {
	frac ret = 1;
	rep(i, 0, n) {
		rep(j, 0, sz(pat[0])) {
			if (pat[i][j] == 1) ret *= prob1(i, offset+j);
			else if (pat[i][j] == 0) ret *= prob0(i, offset+j);
		}
	}
	return ret;
}

frac pattern(const vector<vi>& pat) {
	frac ret = 0;
	rep(offset, -sz(pat[0])+1, m) {
		ret += patternAt(offset, pat);
	}
	return ret;
}

frac solveN1() {
	return pattern({{0,1,0}}) + pattern({{1,1,1,0}});
}

// ---

void run() {
	cin >> n >> m;
	mat.resize(n);
	each(row, mat) {
		cin >> row;
	}

	if (n == 1) {
		cout << solveN1() << '\n';
		return;
	}

	bool piecewise = 1;
	rep(i, 0, n) rep(j, 0, m) {
		if ((i+1)*(j+1) % 5 == 0 && mat[i][j] != '.') {
			piecewise = 0;
			break;
		}
	}

	if (piecewise) {
		cout << solvePiecewise() << '\n';
	} else {
		cout << solveExp() << '\n';
	}
}

int main() {
	cin.sync_with_stdio(0); cin.tie(0);
	cout << fixed << setprecision(10);
	run();
	cout << flush; _Exit(0);
}