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#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<char, pii> pp;

const int N = 2e3+10;
const int C = 27;

int n, m, cc[N][C+10], cr[N][C+10];
char b[N][N];
bool rm[N][N];
bool vc[N+10], vr[N+10];

pii cntr(int i) {
    int x=0, r=-1;
    for (int j=0; j<C; ++j) {
        if (cr[i][j]) ++x, r=j;
    }

    if (x == 1) return {x, r};
    return {-1, -1};
}

pii cntc(int j) {
    int x=0, r=-1;
    for (int i=0; i<C; ++i) {
        if (cc[j][i]) ++x, r=i;
    }

    if (x == 1) return {x, r};
    return {-1, -1};
}

char bc[N+1][N+1];
bool sim(vector<pp> mv) {

    for (auto u : mv) {
        if (u.first == 'K') {
            for (int i=1; i<=n; ++i) {
                bc[i][u.second.first]=char('A'+u.second.second);
            }
        } else {
            for (int j=1; j<=m; ++j) {
                bc[u.second.first][j]=char('A'+u.second.second);
            }
        }
    }
    
    for (int i=1; i<=n; ++i) {
        for (int j=1; j<=m; ++j) assert(b[i][j] == bc[i][j]);
    } return true;
}

void solve() {
    cin>>n>>m;
    for (int i=1; i<=n; ++i) {
        string s; cin>>s;
        for (int j=0; j<m; ++j) b[i][j+1]=s[j];
    }

    queue<pp> q;
    for (int i=1; i<=n; ++i) {
        for (int j=1; j<=m; ++j) ++cr[i][b[i][j]-'A'];
        pii x=cntr(i);
        if (x.first == 1) q.push({'R', {i, x.second}}), vr[i]=true;
    }

    for (int j=1; j<=m; ++j) {
        for (int i=1; i<=n; ++i) ++cc[j][b[i][j]-'A'];
        pii x=cntc(j);
        if (x.first == 1) q.push({'K', {j, x.second}}), vc[j]=true; 
    }

    vector<pp> mv;
    while (!q.empty()) {
        pp x=q.front(); q.pop();
        mv.push_back(x);

        if (x.first == 'R') {
            // row

            int i=x.second.first;
            for (int j=1; j<=m; ++j) {
                if (rm[i][j]) continue;
                rm[i][j]=true;
                --cc[j][b[i][j]-'A'];
                pii x=cntc(j);
                if (x.first == 1 && !vc[j]) {
                    q.push({'K', {j, x.second}});
                    vc[j]=true;
                }
            }
        } else {
            // column

            int j=x.second.first;
            for (int i=1; i<=n; ++i) {
                if (rm[i][j]) continue;
                rm[i][j]=true;
                --cr[i][b[i][j]-'A'];
                pii x=cntr(i);
                if (x.first == 1 && !vr[i]) {
                    q.push({'R', {i, x.second}});
                    vr[i]=true;
                }
            }
        }
    }

    reverse(mv.begin(), mv.end());
    assert((int)mv.size() <= n+m);
    assert(sim(mv));

    cout<<mv.size()<<"\n";
    for (auto u : mv) {
        cout<<u.first<<" "<<u.second.first<<" "<<char(u.second.second+'A')<<"\n";
    }
}

int main() {
    //ios_base::sync_with_stdio(0);
    //cin.tie(NULL);
    //cout.tie(NULL);

    int t=1; //cin>>t;
    while (t--) solve();
}