antitetris

#include <bits/stdc++.h>

using namespace std;

#define int long long
#define ld long double
#define inf 9e18
#define v vector
#define F first
#define S second
#define min(a, b) (a < b ? a : b)
#define max(a, b) (a > b ? a : b)


int n, m;
v<v<char>> a;
v<v<bool>> used;
v<pair<int, int>> coords;
int ok_path = -1;
string path;

void bfs_find(int x, int y, v<pair<int, int>> &coords) {
    queue<pair<int, int>> q, q1;
    char c = a[x][y];
    q.push({x, y});
    while (!q.empty()) {
        int i = q.front().F, j = q.front().S;
        if (i + 1 < n && !used[i + 1][j] && a[i + 1][j] == c) q.push({i + 1, j});
        if (i - 1 >= 0 && !used[i - 1][j] && a[i - 1][j] == c) q.push({i - 1, j});
        if (j + 1 < m && !used[i][j + 1] && a[i][j + 1] == c) q.push({i, j + 1});
        if (j - 1 >= 0 && !used[i][j - 1] && a[i][j - 1] == c) q.push({i, j - 1});
//        q1 = q;
//        for (int u = 0; u < q.size(); u++) {
//            cout << q1.front().F + 1 << " " << q1.front().S + 1 << "  ";
//            q1.pop();
//        }
//        cout << "\n";
        used[i][j] = true;
        coords.push_back({i, j});
        q.pop();
    }
}

bool can(int move, pair<int, int> begin, v<pair<int, int>> c) {
    int dx = begin.F - c[0].F, dy = begin.S - c[0].S;
    for (int i = 0; i < c.size(); i++) {
        c[i].F += dx;
        c[i].S += dy;
    }

    if (move == 1 && c[0].F == 0) return false;
    for (int i = 0; i < c.size(); i++) {
        if (move == 1) c[i].F -= 1;
        if (move == 2) c[i].S -= 1;
        if (move == 3) c[i].S += 1;
    }
    bool ok = true;
    for (int i = 0; i < c.size(); i++) {
        if (c[i].F >= n || c[i].S >= m || c[i].S < 0 || a[c[i].F][c[i].S] != '.') {
            ok = false;
            break;
        }
    }
    if (!ok) return false;
    return true;
}

void dfs(pair<int, int> begin, string p) {
    if (used[begin.F][begin.S]) return;

    if (begin.F == 0) {
        ok_path = begin.S;
        path = p;
        return;
    }
    used[begin.F][begin.S] = true;

    if (ok_path == -1 && can(1, begin, coords)) dfs({begin.F - 1, begin.S}, "D" + p);
    if (ok_path == -1 && can(2, begin, coords)) dfs({begin.F, begin.S - 1}, "R" + p);
    if (ok_path == -1 && can(3, begin, coords)) dfs({begin.F, begin.S + 1}, "L" + p);
//    1 - UP, 2 - LEFT, 3 - RIGHT
}

signed main(signed argc, char* argv[]) {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
//    cout.setf(ios::fixed);
//    cout.precision(6);
//    freopen("input.txt", "r", stdin);
//    freopen("output.txt", "w", stdout);

    cin >> n >> m;
    a.resize(n, v<char> ('.'));
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            cin >> a[i][j];
        }
    }
    v<v<pair<int, int>>> figures;
    used.resize(n, v<bool> (m, false));
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            if (a[i][j] == '.' || used[i][j]) continue;
            used[i][j] = true;
            v<pair<int, int>> coord;
            bfs_find(i, j, coord);
//            for (int k = 0; k < coord.size(); k++) {
//                cout << coord[k].F + 1 << " " << coord[k].S + 1 << "  ";
//            }
//            cout << "\n";
            sort(coord.begin(), coord.end());
            figures.push_back(coord);
        }
    }

    v<pair<int, string>> ans;
    while (figures.size()) {
        bool ersd = false;
        for (int i = 0; i < figures.size(); i++) {
            used.clear();
            used.resize(n, v<bool> (m, false));
            char symbol = a[figures[i][0].F][figures[i][0].S];
            for (int k = 0; k < figures[i].size(); k++) {
                a[figures[i][k].F][figures[i][k].S] = '.';
            }
            coords = figures[i];
            ok_path = -1;
            path = "";
            dfs(figures[i][0], "S");
            if (ok_path == -1) {
                for (int k = 0; k < figures[i].size(); k++) {
                    a[figures[i][k].F][figures[i][k].S] = symbol;
                }
            } else {
                ans.push_back({ok_path, path});
                figures.erase(figures.begin() + i);
                ersd = true;
            }

        }
        if (!ersd) {
            cout << -1;
            return 0;
        }
    }

    cout << ans.size() << "\n";
    for (int i = ans.size() - 1; i >= 0; i--) {
        cout << ans[i].F + 1 << " " << ans[i].S << "\n";
    }

    return 0;
}