Opperators

As Iv'e been journeying through verious texts iv'e come accross simmalar lines of code such as this one a few times:

Code:

---

#define MIN(X,Y) ( ((X) < (Y)) ? (X) : (Y) )

---

Now, I know what this does... to a degree the macro part and format i understand but it's the opperators '?' and ':' I don't have a clue what they mean and none of the texts i'm reading appear to explain it.

K&R calls it the conditional operator, see A7.16 of K&R-2.

a = MIN(x,y)
is
if ( x < y ) a = x ; else a = y;
but in a form you can use in an expression.

Oh ok,

so basicly the '?' is the opperator equivilant of the 'IF' command and ':' is the same as Else, just a little differently written

Yes, but you have to must use them both together and the syntax isn't exactly the same (e.g. the condition goes after the if but before the ?).

You can look up the syntax here: http://en.wikipedia.org/wiki/&#37;3F:

The C++ Standard Library has min() from <algorithm> which does the same thing more safely, without the macro.

http://www.cplusplus.com/reference/algorithm/min.html