/in/foo.c:2:15: error: array type has incomplete element type 'int[]'
    2 | void fun (int a[][],int n){
      |               ^
/in/foo.c:2:15: note: declaration of 'a' as multidimensional array must have bounds for all dimensions except the first
/in/foo.c: In function 'main':
/in/foo.c:25:13: error: type of formal parameter 1 is incomplete
   25 |         fun(a,n);
      |             ^
/in/foo.c:28:42: error: expected ';' before '}' token
   28 |                     printf("%d ",a[i][j])
      |                                          ^
      |                                          ;
   29 |                 }printf("\n");
      |                 ~