题解 | #汽水瓶#

value=[]
result=[]
drinked=[]
n=1

while n!=0:
    n=int(input())
    if n!=0:
        value.append(n)

for i in range(len(value)):
    num=value[i]
    drinked=[]
    while num>=3:
        kong = num%3
        huan = num//3
        drinked.append(huan)
        nextStart=kong+huan
        num=nextStart
    if num==2:
        result.append(sum(drinked)+1)
    else:
        result.append(sum(drinked))

for i in range(len(result)):
    print(result[i])