"Yuxuan Yuan" <24*8*8*3@s*u*e*t*u*a*e*u*a*> wrote: Very sorry, but I'm going to reverse my decision on this point (to make it easier for all to implement): All statements and function prototypes (1st line) must begin at the left-hand-margin (column 1). The statements forming a function's body must be indented with a single tab-character. So, your above example should be flagged as having an invalid/unrecognised middle line. Please reply if this is unclear!