func_code_string: #include <bits/stdc++.h>   using namespace std;   string arr[55], arr2[55];   vector<pair<int, int> > hasil;   int i, j, n, t, tc, r, x, y, k, c;   void tuker_lr(int x, int y) {     arr[x][y] =  U ;     arr[x + 1][y] =  D ;     arr[x][y + 1] =  U ;     arr[x + 1][y + 1] =  D ;   }   void tuker_ud(int x, int y) {     arr[x][y] =  L ;     arr[x][y + 1] =  R ;     arr[x + 1][y] =  L ;     arr[x + 1][y + 1] =  R ;   }   void l_u_ganjil(int x, int y) {     if (arr[x + 1][y] ==  L ) {       tuker_lr(x, y);       hasil.push_back(make_pair(x, y));     } else if (arr[x + 1][y + 1] ==  U ) {       tuker_ud(x + 1, y);       hasil.push_back(make_pair(x + 1, y));       tuker_lr(x, y);       hasil.push_back(make_pair(x, y));     } else {       l_u_ganjil(x + 1, y + 1);       tuker_ud(x + 1, y);       hasil.push_back(make_pair(x + 1, y));       tuker_lr(x, y);       hasil.push_back(make_pair(x, y));     }   }   void u_d_ganjil(int x, int y) {     if (arr[x][y + 1] ==  U ) {       tuker_ud(x, y);       hasil.push_back(make_pair(x, y));     } else if (arr[x][y + 1] ==  L ) {       l_u_ganjil(x, y + 1);       tuker_ud(x, y);       hasil.push_back(make_pair(x, y));     } else {       u_d_ganjil(x - 1, y + 1);       l_u_ganjil(x, y + 1);       tuker_ud(x, y);       hasil.push_back(make_pair(x, y));     }   }   int main() {     scanf( %d %d , &r, &c);     for (i = 0; i < r; i++) cin >> arr[i];     for (i = 0; i < r; i++) cin >> arr2[i];     if (c % 2 == 1) {       for (j = 0; j < c; j++)         for (i = 0; i < r; i++)           if (arr[i][j] ==  L ) l_u_ganjil(i, j);     } else {       for (j = 0; j < c; j++)         for (i = 0; i < r; i++)           if (arr[i][j] ==  U ) u_d_ganjil(i, j);     }     for (j = 0; j < c; j++) {       for (i = 0; i < r; i++) {         if (arr[i][j] == arr2[i][j])           continue;         else if (arr[i][j] ==  U )           u_d_ganjil(i, j);         else           l_u_ganjil(i, j);       }     }     printf( %d n , hasil.size());     for (i = 0; i < hasil.size(); i++)       printf( %d %d n , hasil[i].first + 1, hasil[i].second + 1);   }   