Best way to check if an Array of primitives contains all of the primitives in another Array

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I'm looking for the best way to check if an Array of primitives contains all of the primitives in another Array in Java. For instance:

int[] a = new int[]{1,2};
int[] b = new int[]{1,2,3,4,5};
int[] c = new int[]{2,4,6};

containsAll(b, a); //true
containsAll(a, b); //false
containsAll(c, b); //false

Where containsAll is a function that check if inside the first parameter there is the second parameter!!! I don't want to convert my arrays of int in arrays of Integer in order to use the following method:

Arrays.asList(a).containsAll(Arrays.asList(b))

Because I think that if the arrays are huge, it would be a big waste of performance!!! But maybe I'm wrong and the best solution is that one... Have you got any idea?

arrays java
1 Answers

The containsAll() method from the Java collections framework effectively does the two nested loops, so you'll waste performance converting to ArrayList<Integer> or Integer[] with Arrays.asList() and using containsAll().

Doing two nested loops over your int[] arrays yourself will definitely beat that.

And if you have additional information (e.g. sorted arrays, repeated use of the same arrays, typical sizes of the arrays), a more performant algorithm might be possible.

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