solution

    public static int[] intersectionOfTwoArrays(int[] firstArr, int[] secondArr) {

        if (firstArr.length > secondArr.length) {
            return intersectArrays(firstArr, secondArr);
        } else {
            return intersectArrays(secondArr, firstArr);
        }
    }

    private static int[] intersectArrays(int[] firstArr, int[] secondArr) {
        int[] result = new int[secondArr.length];
        for (int i = 0; i < firstArr.length; i++) {
            for (int j = 0; j < secondArr.length; j++) {
                if (firstArr[i] == secondArr[j]) {
                    result[j] = secondArr[j];
                }
            }
        }

        return result;
    }