#include <bits/stdc++.h>
using namespace std;
const int MOD = (int)1e9 + 7;
const int INF = (int)1e9;
const long long LINF = (long long)1e18;
const long double PI = acos((long double)-1);
const long double EPS = 1e-9;
inline long long gcd(long long a, long long b) {
  long long r;
  while (b) {
    r = a % b;
    a = b;
    b = r;
  }
  return a;
}
inline long long lcm(long long a, long long b) { return a / gcd(a, b) * b; }
inline long long fpow(long long n, long long k, int p = MOD) {
  long long r = 1;
  for (; k; k >>= 1) {
    if (k & 1) r = r * n % p;
    n = n * n % p;
  }
  return r;
}
template <class T>
inline int chkmin(T& a, const T& val) {
  return val < a ? a = val, 1 : 0;
}
template <class T>
inline int chkmax(T& a, const T& val) {
  return a < val ? a = val, 1 : 0;
}
inline long long isqrt(long long k) {
  long long r = sqrt(k) + 1;
  while (r * r > k) r--;
  return r;
}
inline long long icbrt(long long k) {
  long long r = cbrt(k) + 1;
  while (r * r * r > k) r--;
  return r;
}
inline void addmod(int& a, int val, int p = MOD) {
  if ((a = (a + val)) >= p) a -= p;
}
inline void submod(int& a, int val, int p = MOD) {
  if ((a = (a - val)) < 0) a += p;
}
inline int mult(int a, int b, int p = MOD) { return (long long)a * b % p; }
inline int inv(int a, int p = MOD) { return fpow(a, p - 2, p); }
inline int sign(long double x) { return x < -EPS ? -1 : x > +EPS; }
inline int sign(long double x, long double y) { return sign(x - y); }
const int maxn = 50 + 5;
int n, m;
int a[maxn][maxn];
int b[maxn][maxn];
vector<pair<int, int> > ans;
void fix(int u, int v) {
  if (a[u][v] == 'L') {
    if (a[u + 1][v] == 'R') {
      fix(u + 1, v - 1);
    }
    if (a[u + 1][v] == 'U') {
      fix(u + 1, v);
    }
    if (a[u + 1][v] == 'L') {
      ans.push_back(make_pair(u, v));
      a[u][v] = a[u][v + 1] = 'U';
      a[u + 1][v] = a[u + 1][v + 1] = 'D';
    }
  } else if (a[u][v] == 'U') {
    if (a[u][v + 1] == 'D') {
      fix(u - 1, v + 1);
    }
    if (a[u][v + 1] == 'L') {
      fix(u, v + 1);
    }
    if (a[u][v + 1] == 'U') {
      ans.push_back(make_pair(u, v));
      a[u][v] = a[u + 1][v] = 'L';
      a[u][v + 1] = a[u + 1][v + 1] = 'R';
    }
  }
}
void solve() {
  cin >> n >> m;
  for (int i = (0); i < (n); i++) {
    string s;
    cin >> s;
    for (int j = (0); j < (m); j++) a[i][j] = s[j];
  }
  for (int i = (0); i < (n); i++) {
    string s;
    cin >> s;
    for (int j = (0); j < (m); j++) b[i][j] = s[j];
  }
  for (int i = (0); i < (n); i++)
    for (int j = (0); j < (m); j++)
      if (a[i][j] != b[i][j]) {
        fix(i, j);
      }
  cout << int((ans).size()) << "\n";
  for (int i = (0); i < (int((ans).size())); i++) {
    cout << ans[i].first + 1 << " " << ans[i].second + 1 << "\n";
  }
}
int main() {
  ios_base::sync_with_stdio(0);
  solve();
  return 0;
}
