java - How to remove an element and add it at the end of an ArrayList? -

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i'm beginner in java. i'm trying create shuffle method poker game java code. it's supposed return 52 cards, shuffled. instructions tell me remove card using math.random , return @ end of arraylist, , 500 times shuffle it.

i'm confused how can add back. have far... thanks! 

  public void shuffle()   {       int x = (int)(52 * math.random());      mydeck.remove(x);    }

by way, mydeck arraylist name. 

 arraylist<card> mydeck;

you need store result of remove():

card card = mydeck.remove(x);

then add again, automatically places @ end of list:

mydeck.add(card);

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