Count number of values with two criterias

I have two columns one with random values but several values appear twice or more in the column. In the second column I have up to 3 - 4 values the and the values in column A and B are always connected. So what I would like to do is to check how many of the values in colum A matches with at least two values in column B.

I hope I explained it correctly, please the attachment.

Thanks