presto-array/src/main/java/io/prestosql/array/IntBigArrays.java/IntBigArrays/swap
class IntBigArrays:    public static void swap(final int[][] array, final long first, final long second)
    {
        final int t = array[segment(first)][displacement(first)];
        array[segment(first)][displacement(first)] = array[segment(second)][displacement(second)];
        array[segment(second)][displacement(second)] = t;
    }