UniqueArrayFromTwoV2

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ArrayStuff2
{
    class Program
    {
        static void Main(string[] args)
        {
            int[] A = {1,1,1,2,3,4,2,3,4,5,3,6};
            int[] B = {2,5,8,8,7,9,0};

            foreach (int n in new Uniquelizer(A,B).Uniquelize())
                Console.WriteLine(n);
        }

    }

     class Uniquelizer
    {
        private int uniqueCounter = 0;
        private int[] elementCounters = new int[10];

        public Uniquelizer(int[] first, int[] second)
        {
            countNumbersInArray(first);
            countNumbersInArray(second);
        }

        private void countNumbersInArray(int[] array)
        {
            foreach (int n in array)
            {
                if (elementCounters[n] == 0)
                    uniqueCounter++;
                if (elementCounters[n] == 1)
                    uniqueCounter--;
                elementCounters[n]++;
            }
        }

        public int[] Uniquelize()
        {
            int[] result = new int[uniqueCounter];

            for (int i = 0, uniqueIndex = 0; i < 10; i++)
            {
                if (elementCounters[i] == 1)
                {
                    result[uniqueIndex] = i;
                    uniqueIndex++;
                }
            }

            return result;
        }
    }
}