asalamo alikum

frnz plz help me in simple program in gwbasic. mene aik simple program likha tha
10 cls
20 print "absc"
30 print "xyz"
40 print "123"
50 print "000"
run
mjhe ye program run karne k bad dobara list dekhkar us mein se jab mein line number 50 remove karta hon or jub last mein dobara run karta hon to line number 50 dobara ajati hay ye kese theek hoga, plz help ksi dost ko bata na he mujhay.