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# selecting unique numbers

Greenhorn
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Hello everyone,

From a collection of numbers i need to select the unique ones. Is map a good option?will it affect the performance?any other suggestions?
Thanks

Greenhorn
Posts: 14
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HashMap is exactly what you want to achieve you're goal. It will be fast and easy.

Ranch Hand
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Do you mean, for example, {1,2,3,3,4,5,5,5,6,7,7} must result in {1,2,4,6}? That is, only those numbers that are not duplicated.
Or must it result in {1,2,3,4,5,6,7}? That is, only one of each number, removing the duplicates.

Ranch Hand
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A map would be a poor option for the stated objective. I am not saying you cannot use a pair of socks as pot holders, rather, that you should not. What are you mapping? Answer: nothing.

Given an array of int you can generate a unique list as follows:

Set<Integer> set = new HashSet<Integer>();

Deepa Krishnan
Greenhorn
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{1,2,3,3,4,5,5,5,6,7,7} must result in {1,2,3,4,5,6,7} only one of each number, removing the duplicates

Ranch Hand
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Set can be used since you dont want any duplicate items.

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