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1

I am developing an iphone app and I was wondering the following:

How do I initialise an NSMutableArray of NSMutableArrays to a certain size?

Sorry for the noob question

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up vote 8 down vote 
NSMutableArray *array = [[NSMutableArray alloc] initWithCapacity:5];

for (int i = 0; i < 5; i++) {
   NSMutableArray *innerArray = [[NSMutableArray alloc] initWithCapacity:5];

   [array addObject:innerArray];
}
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4  
Note that initWithCapacity: is just setting an initial capacity. The array can continue to grow as much as you like (it's an optimization tool) – Nektarios Jul 17 '11 at 2:51
1  
Of course, it is implied because it is a mutable array. – Wayne Hartman Jul 17 '11 at 3:07
1  
For someone that's new I don't think that's obvious. C arrays are certainly mutable and certainly don't have built-in expansion of available space – Nektarios Jul 17 '11 at 3:10
up vote 3 down vote

You don't set a maximum size. You just keep addObject:'ing to them

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Exactly, NSMutableArray don't need initWithCapacity. Never. – Farini Feb 13 '12 at 21:26

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