/in/foo.c: In function 'main':
/in/foo.c:8:2: warning: implicit declaration of function 'scanf_s'; did you mean 'scanf'? [-Wimplicit-function-declaration]
  scanf_s(%d, &a);
  ^~~~~~~
  scanf
/in/foo.c:8:10: error: expected expression before '%' token
  scanf_s(%d, &a);
          ^
/in/foo.c:15:6: error: 'i' undeclared (first use in this function)
 for (i = 0; i <9 ; i++)
      ^
/in/foo.c:15:6: note: each undeclared identifier is reported only once for each function it appears in