可变数组的二维NSMutableArray，但不知道我需要多少

Question

I have a large array (a few hundred objects), and I need to separate it into several arrays depending on an integer in the object, but I don't know how many arrays I'll need. I thought using a two-dimensional NSMutableArray would work, but if I do it as seen below, then when I empty the tempArray, it empties the array in fullArray as well. Is there another way to use a temporary, reusable array that, once it's been added to another array, it releases references to it.

- (void)createArray{

fullArray=[[NSMutableArray alloc]init];
NSMutableArray *tempArray=[[NSMutableArray alloc] init];

for(int j=0; j<numberOfGames; j++){

    for(int i=0; i<[appDelegate.hiddenChars count]; i++){
        Chars *charObj=[appDelegate.hiddenChars objectAtIndex:i];
        if(charObj.gameID==j){
            //NSLog(@"Match!");
            [tempArray addObject:charObj];
        }
    }
    [fullArray addObject:tempArray];
    [tempArray removeAllObjects];   //this empties it from fullArray too
}

}

I can get a variable for how many rows and columns, but they're not static. I've tried using C arrays, but I won't be able to make a global array that way. I tried defining a global array and using "new" in create array, but Xcode says "new" is unrecognized. I tried

id fullArray;//in global scope
fullArray=new id fullArray[rows][columns];//new and id throw exceptions, new unrecognized and id expects ";" before it.

My other thought is to create a singleton, but it seems like overkill for this problem. Surely there's a way to handle needing an unknown number of arrays?

I'll be using the arrays to populate a grouped tableview with multiple sections. Maybe I'm going about this all wrong?

Thanks for any help.

Answer 1

Change just about 2 lines and you've got it.

- (void)createArray{

    fullArray=[[NSMutableArray alloc]init];

    for(int j=0; j<numberOfGames; j++){
        // inside loop
        NSMutableArray *tempArray=[[NSMutableArray alloc] init];

        for(int i=0; i<[appDelegate.hiddenChars count]; i++){
            Chars *charObj=[appDelegate.hiddenChars objectAtIndex:i];
            if(charObj.gameID==j){
                //NSLog(@"Match!");
                [tempArray addObject:charObj];
            }
        }
        [fullArray addObject:tempArray];
        [tempArray release]; // but fullArray still owns it
    }

}