请高手帮忙看看这道题
写出下面程序的运行结果____。 10 READ k
IF k<0 THEN 20
READ m
IF m<0 THEN 20
FOR i=1 TO k STEP m
a=a+k
NEXT i
GOTO 10
20 PRINT "a=";a
DATA 5,4,2,1,3,3,-1
END
a=18/18/19/16
2008-04-03 22:27
2008-04-04 10:18
2008-04-05 19:17
2008-04-05 21:18
2008-05-20 18:47