def SelElev(N) :
waitfloor = getquene()
dist = 999 //初始化距離
m = 999 //選定的電梯
for num in range(1,N) :
runfloor = getcurfloor(num)
if abs(waitfloor-runfloor) <= dist //距離較近的電梯
dist = runfloor
m = num
return m