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iOS Build a Blog Reader iPhone App Getting Data from the Web Mutable vs Immutable

Posted by Michael Wang
Michael Wang
4,482 Points

Code challenge: Mutable vs. Immutable 4 of 4

I test my code in Xcode it works but still wrong in this challenge.

NSMutableArray *elements = [NSMutableArray array];
elements = [ NSMutableArray arrayWithObjects:@"Helium",
                    @"Neon",
                    @"Argon",@"Will",nil];
[elements removeObjectAtIndex:1];
[elements removeObjectAtIndex:[elements count]-1];

1 Answer

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

your code is correct, however it seems the challenge is expecting you to use the removeLastObject instance method of NSMutableArray, instead of using the count method. so try using the removeLastObject method instead

you should also remove that extra object you have in your array: @"will", you dont need that

[ NSMutableArray arrayWithObjects:@"Helium", @"Neon", @"Argon",nil];
Michael Wang
Michael Wang
4,482 Points

Thanks, Stone.