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iOS Object-Oriented Objective-C Memory, Arrays and Loops, Oh My! Review Dictionaries and Arrays

how add values from NSArray to NSMutableDictionary using objectAtIndex?

The keys to the values has to 'customer', 'size', 'style' and 'color'

variable_assignment.mm
NSArray *shoeOrder = @[@"Charles Smith",@9.5,@"loafer",@"brown"];
NSString *customer = [shoeOrder objectAtIndex:0];
NSNumber *size = [shoeOrder objectAtIndex:1];
NSString *style = [shoeOrder objectAtIndex:2];
NSString *color = [shoeOrder objectAtIndex:3];

NSMutableDictionary *shoeOrderDict = [[NSMutableDictionary alloc]initWithObjectsAndKeys:@"customer",@"size",@"style",@"color",nil];

1 Answer

Hi Andrea,

So you got the shoeOrder array correct. All this Challenge is asking you to do from there is to create a new instance of NSMutableDictionary called shoeOrderDict ...

NSMutableDictionary *shoeOrderDict = [[NSMutableDictionary alloc]init];

... and then assign the appropriate key — from the keys provided — to the corresponding value from the shoeOrder array, like this:

shoeOrderDict[@"customer"] = [shoeOrder objectAtIndex: 0];
shoeOrderDict[@"size"] = [shoeOrder objectAtIndex: 1];
shoeOrderDict[@"style"] = [shoeOrder objectAtIndex: 2];
shoeOrderDict[@"color"] = [shoeOrder objectAtIndex: 3];