/in/foo.cc: In function 'int gjd(int*, int, int)':
/in/foo.cc:4:6: warning: unused variable 'jw' [-Wunused-variable]
  int jw=0;
      ^~
/in/foo.cc:6:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:11:8: error: 'jc' was not declared in this scope
  n=jc(n);
        ^
/in/foo.cc:10:6: warning: unused variable 'a' [-Wunused-variable]
  int a[9999];
      ^