/in/foo.c:3:1: warning: data definition has no type or storage class
 a=16
 ^
/in/foo.c:3:1: warning: type defaults to 'int' in declaration of 'a' [-Wimplicit-int]
/in/foo.c:4:1: error: expected ',' or ';' before 'b'
 b=input
 ^