the question mark is used as a conditional symbol. For example, in the expression x1 ? x2 : x3, if x1 is not zero, then x2 is evaluated, otherwise x3 is evaluated. THIS DEFINITION IS FOR PERSONAL ...

A question mark ( ? ) is used to close a direct question. (What time is it?) Do not use a question mark with an indirect question. (He asked if we knew the time.) Put a question mark inside closing ...