objective c compare range intersect

Question

I am trying to find the intersection of 2 number ranges, say for example...

range A is from 10 to 100, range B is from 60 to 70

Is there an easy way without writing a load of if statements to calculate the intersection of the two ranges, so in this example it would be 10.

Thanks,

Answer 1

If you have or make NSRange objects, the NSIntersectionRange function will do this for you. Just be sure to check what it returns when there is no intersection.

NSRange a = NSMakeRange(10, 90);
NSRange b = NSMakeRange(60, 10);
NSRange intersection = NSIntersectionRange(a, b);
if (intersection.length <= 0)
    NSLog(@"Ranges do not intersect");
else
    NSLog(@"Intersection = %@", NSStringFromRange(intersection));

Answer 2

You can use this method for that purpose:

NSRange NSIntersectionRange (
   NSRange range1,
   NSRange range2
);

You can find all the info here:

NSIntersectionRange Apple Doc