fb编程求 sn=a+aa+aaa+```+的值
将下列程序补充完整.
求 sn=a+aa+aaa+```+的值(例如 ,当a=2,n=4时,sn=2+22+222+2222）.
dim as integer a,n
input "a,n=",a,n
s=0:t=0
for i = 1 to ()
t=()
s=s+t
next i
print "s=";s
sleep
end