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#include <bits/stdc++.h>


using namespace std;


const long long V = 24;


long long solveNoWildcards(int n, int m, vector <vector<int>> &tab) {
    for (auto &e : tab) for (auto &f : e) assert(f != -1);

    vector <vector<int>> val(n, vector <int> (m, 0.0));
    for (int x = 0; x < n; x++) for (int y = 0; y < m; y++) if (tab[x][y]) {
        val[x][y] = V;
    }

    int dx[] = {0, 1, 0, -1};
    int dy[] = {1, 0, -1, 0};

    while (true) {
        vector <tuple<int,int,int>> decr;

        for (int x = 0; x < n; x++) for (int y = 0; y < m; y++) if (val[x][y]) {
            int deg = 0;
            for (int dir = 0; dir < 4; dir++) {
                int nx = x + dx[dir], ny = y + dy[dir];
                if (nx >= 0 && nx < n && ny >= 0 && ny < m && val[nx][ny]) {
                    deg++;
                }
            }

            if (deg > 0) {
                decr.push_back({x, y, deg});
            }
        }

        if (decr.empty()) {
            break;
        }

        int time = V;
        for (auto &[x, y, deg] : decr) {
            assert(val[x][y] % deg == 0);
            time = min(time, val[x][y] / deg);
        }

        for (auto &[x, y, deg] : decr) {
            val[x][y] -= time * deg;
        }
    }

    long long totalLeft = 0;
    for (int x = 0; x < n; x++) for (int y = 0; y < m; y++) if (tab[x][y]) {
        totalLeft += val[x][y];
    }

    return totalLeft;
}

pair <long long, long long> constructAns(long long num, long long denom) {
    long long gcd = __gcd(num, denom);
    return {num / gcd, denom / gcd};
}

pair <long long, long long> solve(int n, int m, vector <vector<int>> &tab) {
    vector <pair<int,int>> wildcards;
    for (int x = 0; x < n; x++) for (int y = 0; y < m; y++) if (tab[x][y] == -1) {
        wildcards.push_back({x, y});
    }

    int numWildcards = wildcards.size();

    if (n == 1) {
        long long ansTotal = 0;

        auto numWildcardsInside = [&](int l, int r) {
            int cnt = 0;
            for (int i = max(0, l); i <= min(m - 1, r); i++) if (tab[0][i] == -1) {
                cnt++;
            }

            return cnt;
        };

        auto canBeEmpty = [&](int y) { return y < 0 || y >= m || tab[0][y] != 1; };
        auto canBeFilled = [&](int y) { return y >= 0 && y < m && tab[0][y] != 0; };

        for (int y = 0; y < m; y++) if (canBeFilled(y) && canBeEmpty(y + 1)) {
            ansTotal += 1 << (4 - numWildcardsInside(y, y + 1));
        }

        for (int y = 0; y < m - 1; y++) {
            if (canBeEmpty(y - 1) && canBeFilled(y) && canBeFilled(y + 1) && canBeEmpty(y + 2)) {
                ansTotal -= 1 << (4 - numWildcardsInside(y - 1, y + 2));
            }
        }

        return constructAns(ansTotal, 16);
    } else if (numWildcards <= 5) {
        long long ansTotal = 0;
        for (int mask = 0; mask < (1 << numWildcards); mask++) {
            auto tabConcrete = tab;
            for (int i = 0; i < numWildcards; i++) {
                auto [x, y] = wildcards[i];
                if (mask & (1 << i)) {
                    tabConcrete[x][y] = 1;
                } else {
                    tabConcrete[x][y] = 0;
                }
            }

            ansTotal += solveNoWildcards(n, m, tabConcrete);
        }

        return constructAns(ansTotal, V * (1 << numWildcards));
    } else {
        bool segmented = true;
        for (int x = 0; x < n; x++) for (int y = 0; y < m; y++) {
            int prod = (x + 1) * (y + 1);
            if (prod % 5 == 0 && tab[x][y] != 0) {
                segmented = false;
            }
        }

        assert(segmented);

        const int F = 4;
        const int FMASKS = 1 << (F * F);

        vector <long long> allAnswers(FMASKS, 0);

        vector <vector<int>> tabSlice(F, vector <int> (F));
        for (int mask = 0; mask < FMASKS; mask++) {
            for (int x = 0; x < F; x++) for (int y = 0; y < F; y++) {
                int idx = x * F + y;
                tabSlice[x][y] = (mask & (1 << idx)) != 0;
            }

            allAnswers[mask] = solveNoWildcards(F, F, tabSlice);
        }

        long long ansTotal = 0;
        for (int xs = 0; xs < n; xs += F + 1) for (int ys = 0; ys < m; ys += F + 1) {
            int maskOn = 0, maskWildcard = 0;
            for (int x = 0; x < F; x++) for (int y = 0; y < F; y++) {
                int idx = x * F + y, xReal = xs + x, yReal = ys + y;
                if (xReal < n && yReal < m) {
                    if (tab[xReal][yReal] == 1) {
                        maskOn |= 1 << idx;
                    } else if (tab[xReal][yReal] == -1) {
                        maskWildcard |= 1 << idx;
                    }
                }
            }

            int nw = __builtin_popcount(maskWildcard);
            for (int mask = 0; mask < FMASKS; mask++) {
                if ((mask & maskOn) == maskOn) {
                    int rest = mask ^ maskOn;
                    if ((rest & maskWildcard) == rest) {
                        ansTotal += allAnswers[mask] << (F * F - nw);
                    }
                }
            }
        }

        return constructAns(ansTotal, V * FMASKS);
    }
}

int main() {
    ios_base::sync_with_stdio(false);

    int n, m;
    cin >> n >> m;

    vector <vector<int>> tab(n, vector <int> (m));
    for (int i = 0; i < n; i++) {
        string s;
        cin >> s;

        for (int j = 0; j < m; j++) {
            if (s[j] == 'O') {
                tab[i][j] = 1;
            } else if (s[j] == '?') {
                tab[i][j] = -1;
            } else {
                tab[i][j] = 0;
            }
        }
    }

    auto [x, y] = solve(n, m, tab);
    cout << x << "/" << y << '\n';

    return 0;
}