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What's the Best Way to Shuffle an NSMutableArray?

I have some values in a NSMutableArray. Now i need to shuffle these values. Can someone tell me how to shuffle these values.

Sorry i don't have any code to demonstrate.

I went through this SO post, which suggest to use exchangeObjectAtIndex:withObjectAtIndex:, but can someone show me how it is done. An example or a tutorial which explains this would help.

Community
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Illep
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    Why didn't you look at the other answers for that question?? [One of them](http://stackoverflow.com/a/56656/689356) provides a complete solution. – yuji Apr 01 '12 at 15:50

1 Answers1

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You can do it like this: 

for (int i = [array count] - 1; i > 0; i--) {
    int j = arc4random() % (i+1);
    [array exchangeObjectAtIndex:i withObjectAtIndex:j];
}

array is Your NSMutableArray.

Justin Boo
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  • For a good shuffle, you don't want to mod with `array count` but with `i`. See [the Fisher-Yates shuffle‌​](http://en.wikipedia.org/wiki/Fisher-Yates_shuffle#The_modern_algorithm). – SSteve Apr 01 '12 at 16:13