public static int[] removeDuplicates(int[] input) {
        int arrayLength = input.length;
        Integer[] nums = new Integer[arrayLength];
        for (int el : input) {
            if (!doesElementExistInArray(el, nums)){
                addToArray(el, nums);
            }
        }
        int[] array = new int[nums.length];

        for(int i = 0; i < nums.length; i++) {
            array[i] = nums[i].intValue();
        }

        return array;
    }
    public static boolean doesElementExistInArray(int num, Integer[] arr){
        for (int i = 0; i < arr.length; i++) {
            if (arr[i] == num)
                return true;
        }
        return false;
    }
    public static Integer[] addToArray(int num, Integer[] arr){
        for (int i = 0; i < arr.length; i++){
            if (arr[i] == null)
                arr[i] = num;
            return arr;
        }
        return arr;
    }