How to do multiplication and addition with NSNumber
nsnumber, objective-c
Solution
There is no explicit support for doing math operations on `NSNumber`. `NSNumber` is used to wrap a primitive type number. (e.g. use it for storing in arrays/dicitionaries)
If you have an `NSNumber` instance and you want to make math operations you should extract its value into a primitive type :
int num = [numberInstance intValue];
num += 1; // Just for the example;
After you are done create a new instance for storing the new value (since `NSNumber` is immutable you cannot use the old `NSNumber` instance)
numberInstance = [NSNumber numberWithInt:num];
Problem
I want to implement simple calculation with NSNumber. For ex: ``` int a; a=a*10; a=a+1; NSLog(@"%d",a); ``` How to do the same thing if i declare ``` NSNumber *a; ``` I want to implement the same logic with NSNumber which I implemented using integer. Thanks