Hello sir: Here's the data: a b c d 1 2 3 4 I wanna know how to get: ab ac ad bc bd cd 12 13 14 23 24 34 Thanks a lot! My best ------------------------------ ******************************************* Xin Meng Capitalbio Corporation National Engineering Research Center for Beijing Biochip Technology BioPharma-informatics & Software Dept. Research Engineer Tel: +86-10-80715888/80726868-6438 Fax: +86-10-80726790 Email??xmeng at capitalbio.com Address:18 Life Science Parkway, Changping District, Beijing 102206, China