Off topic:Pairwise comparison of dataframe rows in R

Question

[OdongoR89]

Hello family! I have a dataframe like this:

n

ame       members
x1            A,B,N,K,Y,G
x2            J,L,M,N,T
x3            G,H,S,J,D,F
x4            J,K,H,F,H,D,L

I want to perform pairwise comparison to find the number of common elements between any two rows like below:

name         common       name
x1                   6               x1
x1                   2               x2
x1                     -             x3
x1                      -            x4
x2                       -           x1
x2                5        -          x2
x2                         -         x3
x2                          -        x4
x3                           -       x1
x3                            -      x2
x3                   6          -     x3
x3                              -    x4
x4                               -   x1
x4                                -  x2
x4                                 - x3
x4                  7                -x4

I notice that the exact orientation of the dataframe is not writable in this workspace, but treat former as a 4by1 matrix and the later as a 16by3 matrix