Pesky Doubles

public static void ridOfDoubles(ref int[] arr)
        {

            int count = 0;

            for (int i = 0; i < arr.Length; i++)
            {
                for (int j = 1; j < arr.Length; i++)
                {
                    if (arr[i] == arr[j])
                    {
                        arr[j] = -1; // Marks for deletion
                        count++;
                    }
                }
            }

            for (int i = 0; i < arr.Length; i++)
            {
                if (arr[i] == -1)
                {
                    for (int j = i + 1; j < arr.Length; i++)
                    {
                        arr[j - 1] = arr[j];
                    }
                }
            }

            Array.Resize(ref arr, arr.Length - count);
        }