Python中逆序输出字符串的六种方法

方法一：直接使用字符串切片功能逆转字符串

#!usr/bin/env python
# encoding:utf-8
def strReverse(strDemo):
  return strDemo[::-1]
print(strReverse('pythontab.com'))

方法二：遍历构造列表法

#!usr/bin/env python
# encoding:utf-8
def strReverse(strDemo):
  strList=[]
  for i in range(len(strDemo)-1, -1, -1):
    strList.append(strDemo[i])
  return ''.join(strList)
print(strReverse('pythontab.com'))

方法三：使用reverse函数

#!usr/bin/env python
# encoding:utf-8
def strReverse(strDemo):
  strList = list(strDemo)
  strList.reverse()
  return ''.join(strList)
print(strReverse('pythontab.com'))

方法四：借助collections模块方法extendleft

#!usr/bin/env python
# encoding:utf-8
import collections
def strReverse(strDemo):
  deque1=collections.deque(strDemo)
  deque2=collections.deque()
  for tmpChar in deque1:
    deque2.extendleft(tmpChar)
  return ''.join(deque2)
print(strReverse('pythontab.com'))

方法五：递归实现

#!usr/bin/env python
# encoding:utf-8
def strReverse(strDemo):
  if len(strDemo)<=1:
    return strDemo
  return strDemo[-1]+strReverse(strDemo[:-1])
print(strReverse('pythontab.com'))

方法六：借助基本的Swap操作，以中间为基准交换对称位置的字符

#!usr/bin/env python
#encoding:utf-8
  
def strReverse(strDemo):
  strList=list(strDemo)
  if len(strList)==0 or len(strList)==1:
    return strList
  i=0
  length=len(strList)
  while i < length/2:
    strList[i], strList[length-i-1]=strList[length-i-1], strList[i]
    i+=1
  return ''.join(strList)
print(strReverse('pythontab.com'))