[R] intersect() question

[Andrej Kastrin]

Hi,

I have a matrix containing ID numbers in each column. I would like to 
program function which calculate common number of ID numbers between 
each pair of columns.

Suppose:

5 6 7
1 5 3
6 7 2

Then the result should be:

0 2 0
2 0 1
0 1 0

The main problem is how to implement intersect() function to walk 
through each pair of columns and write result to result matrix.

Thanks in advance for any suggestion, Andrej