我正在尝试使用Python 2.7使用合并排序算法更好地理解递归。我写了一小段代码来递归地分解列表。除了最后一步,代码似乎工作正常。对于基本情况,程序应该返回大小为1的列表。但是,它返回值“none”。我哪里错了?
mylist = [14,88,2,14,9,123,1,5]
def concour(thelist):
mid = len(thelist) / 2
LeftSide = thelist[:mid]
print LeftSide,'length is ', len(LeftSide)
if len(LeftSide) == 1: #the base case here
print LeftSide
return LeftSide
else:
concour(LeftSide) #recursive call
print concour(mylist)
"""
[14, 88, 2, 14] length is 4
[14, 88] length is 2
[14] length is 1
[14]
None
"""
答案 0 :(得分:1)
您在递归调用中错过了返回语句。