用python语言实现“连续邮资”问题的回溯算法

用python语言实现“连续邮资”问题的回溯算法，怎么求？
求解答…

Max = 4 
Prices = [0,1,3,11,15,32] # 单价列表

def Traceback(count):
    global tmp,flag,Result
    if count==Max:
        if tmp == Result+1:
            flag = True
        return
    for i in range(len(Prices)):
        tmp += Prices[i]
        if tmp <= Result+1:
            Traceback(count+1)
        tmp -= Prices[i]

Result = 0
tmp = 0

while True:
    flag = False
    Traceback(0)
    if flag:
        Result += 1
    else:
        break

print(Result)