#include <bits/stdc++.h>
using namespace std;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const long long N = 55;
long long n, m;
vector<pair<long long, long long>> solve(vector<string> a) {
  vector<pair<long long, long long>> ret;
  auto move = [&](long long x, long long y) {
    ret.push_back(make_pair(x, y));
    if (a[x][y] == 'L') {
      a[x][y] = a[x][y + 1] = 'U';
      a[x + 1][y] = a[x + 1][y + 1] = 'D';
    } else if (a[x][y] == 'U') {
      a[x][y] = a[x + 1][y] = 'L';
      a[x][y + 1] = a[x + 1][y + 1] = 'R';
    } else {
      assert(0);
    }
  };
  cerr << m << endl;
  function<void(long long, long long)> go = [&](long long x, long long y) {
    if (a[x][y] == 'L') return;
    assert(a[x][y] == 'U');
    if (a[x][y + 1] == 'U') {
      move(x, y);
    } else if (a[x][y + 1] == 'L') {
      go(x + 1, y + 1);
      move(x, y + 1);
      move(x, y);
    } else {
      assert(0);
    }
    assert(a[x][y] == 'L');
  };
  if (m % 2 == 0) {
    for (long long i = 0; i + 1 < n; i += 2) {
      for (long long j = 0; j < m; j += 2) {
        if (a[i][j] == 'L') {
          assert(a[i][j + 1] == 'R');
          if (a[i + 1][j] != 'L') {
            assert(a[i + 1][j] == 'U');
            go(i + 1, j);
          }
        } else if (a[i][j] == 'U') {
          if (a[i][j + 1] == 'U') {
            move(i, j);
          } else {
            assert(a[i][j + 1] == 'L');
            go(i + 1, j + 1);
            move(i, j + 1);
            move(i, j);
          }
        } else {
          assert(0);
        }
      }
    }
  } else {
    for (long long j = 0; j + 1 < m; j += 2) {
      for (long long i = 0; i < n; i += 2) {
        if (a[i][j] == 'L') {
          go(i + 1, j);
          move(i, j);
        } else if (a[i][j] == 'U') {
          if (a[i][j + 1] != 'U') {
            assert(a[i][j + 1] == 'L');
            go(i + 1, j + 1);
            move(i, j + 1);
          }
        } else {
          assert(0);
        }
      }
    }
  }
  return ret;
}
signed main() {
  ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
  cin >> n >> m;
  vector<string> a(n), b(n);
  for (long long i = 0; i < n; i++) {
    cin >> a[i];
  }
  for (long long i = 0; i < n; i++) {
    cin >> b[i];
  }
  auto A = solve(a);
  auto B = solve(b);
  reverse((B).begin(), (B).end());
  A.insert(A.end(), (B).begin(), (B).end());
  cout << (long long)A.size() << '\n';
  for (auto it : A) {
    long long x, y;
    tie(x, y) = it;
    cout << x + 1 << ' ' << y + 1 << '\n';
  }
}
