python翻转字符串

将s = “abcd” 反转为 “dcba”

第一种 字符串切片

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result = s[::-1]

第二种 列表的reverse方法

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l = list(s)
result = "".join(l.reverse())

第三种 for循环

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def (s):
result = ""
max_index = len(s)-1
for index,value in enumerate(s):
result += s[max_index-index]
return result
result = func(s)

第四种 栈

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def (s):
l = list(s)
result = ""
while len(l)>0:
result += l.pop() #出栈
return result
result = func(s)

第五种 递归

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def (s):
if len(s) <1:
return s
return func(s[1:])+s[0]
result = func(s)

第六种 reduce方法

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result = reduce(lambda x,y:y+x,s)