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iOS

How to access a certain digit in a large number?

lets say I have the number 123456789 and I want to do something with the digits 2, 4, 6 and 8. How am I supposed to do that?

2 Answers

Amitai Zand
Amitai Zand
12,513 Points

Perhaps you could convert the entire number into a string and then access individual digits by their index. (At least this is how one could do it using Python or JavaScript; I haven't taken any iOS courses yet but I would assume this method is possible using Objective C).

NSNumber *number = @123456789;
NSString *numberString = [NSString stringWithFormat:@"%@", number];
int index = 0; // Change the value here to access each digit as if an array.
NSString *digit = [numberString substringWithRange:NSMakeRange(index, 1)];