-- coding: utf-8 --

def triangles(): num = [1] while True: temp = num[:] yield temp for i in range(len(num)): if i != 0: num[i] = temp[i] + temp[i-1] num.append(1)

还有什么能简写的地方吗？

#2 Created at ... [Delete] [Delete and Lock User]

def triangles(): num = [1] while True: yield num num = [num[i] + num[i-1] for i in range(len(num))if i != 0] num.append(1) num.insert(0,1)

把for循环和里面的内容整合在一个列表生成式里面，直接生成num，就避免了需要建一个temp来保存当前num值的情况。但是需要num.insert(0,1)来为其添加第一个值。

#3 Created at ... [Delete] [Delete and Lock User]

temp = num[:] 请问这里如果写成temp = num，结果为什么是i个值的和而不是i和i-1的和呢

#4 Created at ... [Delete] [Delete and Lock User]

因为如果是temp = num，那么相当于temp和num指向了同一个对象，这样如果num改变，temp会跟着改变，所以需要用temp = num[:]来复制一个当前num的副本，这样num改变就不会影响到temp的值。

#5 Created at ... [Delete] [Delete and Lock User]

非常感谢，切片看的不够仔细

#6 Created at ... [Delete] [Delete and Lock User]

请问这里的不用num[:]为何之前的list里的数据也会改变

#7 Created at ... [Delete] [Delete and Lock User]

如果temp = num。因为num指向的对象发生改变了，而同样指向这个对象的temp所表达的结果自然也改变了

#8 Created at ... [Delete] [Delete and Lock User]

大神，我把yield temp改成了yield num,结果就不对了，我理解是传回去results的是地址，内容变了，所以最后results的内容也变了，那您写的yield temp传去的应该也是temp的地址吧，如果temp内容变了，那results岂不要一起变，求大神指点下

def triangles(): num = [1] while True: temp = num[:] yield num for i in range(len(num)): if i != 0: num[i] = temp[i] + temp[i-1] num.append(1)

#9 Created at ... [Delete] [Delete and Lock User]

你可以改成range(1,len(num))，就不要if判断了

#10 Created at ... [Delete] [Delete and Lock User]

def triangles(): L = [1] while True: yield L L = [L[0]] + [L[i] + L[i+1] for i in range(len(L)-1)] + [L[-1]]