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code challenge: Mutable vs. Immutable 3 of 4

I can not figure out what I am missing:

NSMutableArray *elements = [NSMutableArray arrayWithCapacity : 0];
elements = [NSMutableArray arrayWithObjects:@"Helium", @"Neon", @"Argon", nil];
elements = [title removeObjectAtIndex: 1];

4 Answers

John Hill
.a{fill-rule:evenodd;}techdegree seal-36
John Hill
Front End Web Development Techdegree Graduate 35,236 Points

Watch the video, you must. The answers you seek lie deep within you (@~3:15 in the video).

NSMutableArray *elements = [NSMutableArray array];
elements = [NSMutableArray arrayWithObjects:@"Helium", @"Neon", @"Argon", nil];
[elements removeObjectAtIndex: 1];
[elements removeLastObject];
Amit Bijlani
Amit Bijlani
Treehouse Guest Teacher

Brian your array is called elements so why in your last line are you calling the method removeObjectAtIndex on something called title? It should be called on elements.

Got it thanks.

i don't get it, please can you kindly advise the 3rd & 4th challenge answers so that i can complete the test