Unique Number - II Concept

How can we get the unique number from this [1,2,3,3,3,2] as 3^3^3 = 3 and we already have 1 as unique?

@Ans According to the question, it was given that all numbers are present twice except 2 numbers which are only once. The solution given in the lecture will only work for this case.
Here in this question you are taking 3 thrice so it cannot be done using this method. So this can be done using brute force only.