/in/foo.c: In function 'main':
/in/foo.c:56:6: warning: implicit declaration of function 'sc' [-Wimplicit-function-declaration]
      sc(top,0);
      ^~
/in/foo.c: In function 'sc':
/in/foo.c:66:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^