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sorting arrays in descending order  RSS feed

 
Greenhorn
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Real quick questions... How do I sort an array of int in descending order. Thanks for any help you can give.
 
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Originally posted by Kevin Knight:
Real quick questions... How do I sort an array of int in descending order. Thanks for any help you can give.



Quick (and hopefully correct) answer: Transfer over to an Integer array, then use Arrays.sort using an appropriate Comparator<Integer> object.

For instance:

[ June 28, 2008: Message edited by: pete stein ]
 
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Welcome to JavaRanch

Pete has already given you the "correct" answer; now I shall give you the answer you want for homework.

Write a class called ArrayUtil or similar and in it implement a public static void swapPair(int[] array, int index1, int index2) method. Pass an array and the numbers of the two elements you want to swap to it. That will swap the two elements. Remember you need a temporary element in the method which will hold the original value while you swap.

Implement a public static void sort(int[] array) method which takes one of the better-known sorting algorithms. Several links to sorting algorithms available: see which of these is most useful: 1 2 3. Lots more available on Google.

Probably best to implement a public static void reverse(int[] array) method which uses the swap method you have already written to reverse the array; that is better than swapping < for > in the sort method.

Use the sort method then the reverse method. And lots of nice marks for you!
 
Kevin Knight
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thanks guys
 
Campbell Ritchie
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Originally posted by Kevin Knight:
thanks guys

You're welcome
 
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