One small problem: you forgot to increment t1 and t2 inside the for loop. -------- Rick Genter BBN Laboratories Inc. (617) 497-3848 10 Moulton St. 6/512 rgenter at labs-b.bbn.COM (Internet new) Cambridge, MA 02238 rgenter at bbn-labs-b.ARPA (Internet old) linus!rgenter%BBN-LABS-B.ARPA (UUCP)