Main.c:2:1: error: unknown type name 'string'
    2 | string canCleanAllRooms(int k, int a, int b) {
      | ^~~~~~
Main.c: In function 'canCleanAllRooms':
Main.c:4:18: warning: implicit declaration of function '__gcd' [-Wimplicit-function-declaration]
    4 |     int gcd_bk = __gcd(b, k);
      |                  ^~~~~
Main.c:7:16: warning: returning 'char *' from a function with return type 'int' makes integer from pointer without a cast [-Wint-conversion]
    7 |         return "Yes";
      |                ^~~~~
Main.c:9:16: warning: returning 'char *' from a function with return type 'int' makes integer from pointer without a cast [-Wint-conversion]
    9 |         return "No";
      |                ^~~~
Main.c: In function 'main':
Main.c:16:5: error: 'cin' undeclared (first use in this function)
   16 |     cin >> k >> a >> b;
      |     ^~~
Main.c:16:5: note: each undeclared identifier is reported only once for each function it appears in
Main.c:18:5: error: 'cout' undeclared (first use in this function)
   18 |     cout << canCleanAllRooms(k, a, b) << endl;
      |     ^~~~
Main.c:18:42: error: 'endl' undeclared (first use in this function)
   18 |     cout << canCleanAllRooms(k, a, b) << endl;
      |                                          ^~~~