#include<bits/stdc++.h>
using namespace std;
using ll = long long;

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    ios::sync_with_stdio(false);
    cin.tie(0);
    int h, w;
    cin >> h >> w;
    vector<string> A(h), B(w, string(h, '?'));
    vector<pair<int,int>> ans;
    vector<vector<int>> C(h, vector<int>(w, 0));
    for(int y = 0; y < h; y++){
        auto &&ss = A[y];
        cin >> ss;
        for(int i = 0; i < w; ){
            int p = i;
            while(i < w && ss[i] == ss[p]) i++;
            if(ss[p] == '#') continue;
            if(i - p >= 2) ans.emplace_back(y, p), C[y][p] |= 1;
        }
    }
    for(int y = 0; y < h; y++){
        for(int x = 0; x < w; x++){
            B[x][y] = A[y][x];
        }
    }
    for(int x = 0; x < w; x++){
        auto &&ss = B[x];
        for(int i = 0; i < h; ){
            int p = i;
            while(i < h && ss[i] == ss[p]) i++;
            if(ss[p] == '#') continue;
            if(i - p >= 2) ans.emplace_back(p, x), C[p][x] |= 2;
        }
    }
    sort(ans.begin(), ans.end());
    ans.erase(unique(ans.begin(), ans.end()), ans.end());

    for(auto &&s : A){
        for(int x = 0; x < w; x++){
            if(s[x] == '.') s[x] = 'a';
        }
    }

    auto ext_x = [&](int y, int x) -> string {
        if(~C[y][x] & 1) return "-";
        string res;
        while(x < w && A[y][x] != '#') res += A[y][x++];
        return res;
    };
    auto ext_y = [&](int y, int x) -> string {
        if(~C[y][x] & 2) return "-";
        string res;
        while(y < h && A[y][x] != '#') res += A[y++][x];
        return res;
    };

    cout << ans.size() << '\n';
    for(auto [y, x] : ans){
        cout << ext_x(y, x) << ' ' << ext_y(y, x) << '\n';
    }
    
}