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 count = 0;

      for(int i = 0; i < nums.length; i++) {
         if(nums[i] == null)
            continue;
         count++;
      }
      int[] array = new int[count];
      for(int i = 0; i < count; i++) {
         array[i] = nums[i];
      }

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