Method swap

java/0347-top-k-frequent-elements.java:86–90

(int[] array, int i1, int i2)

    }

    private void swap(int[] array, int i1, int i2) {
        int temp = array[i1];
        array[i1] = array[i2];
        array[i2] = temp;
    }
}
class Solution3 {
     /**