Question

I have a string which is a 13 digit number. I need to separate all the digits and find the sum of the individual digits. How can I do that?

I converted the string to NSArray like this :

NSArray *arrStrDigits = [str13DigitNumber componentsSeparatedByString:@""];

now I want to run a loop and get something like arrStrDigits[i]

I am new to Objective C :(. Please help me out!

Answer 1

Get the individual digits like this:

unichar digitChar = [str13DigitNumber characterAtIndex: someIndex];
// Should put in some validation that you have a digit here
int digit = digitChar - '0';

That just needs to go in a loop where you iterate someIndex from 0 to [str13DigitNumber length]