How to reverse the specified string in python

Python's method of reversing the specified string: 1. Directly use the string slicing function to reverse the string; 2. Traverse the construction list method; 3. Use the reverse function to implement; 4. Use the collections module method extendleft; 5. Use recursion.

Python method to reverse the specified string:

Method 1: Use string slicing directly Function to reverse string

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

Result:

moc.batnohtyp

Method 2: Traversal construction list method

Loop through the string, construct a list, add elements from back to front, and finally turn the list into a string

#!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'))

Result:

moc.batnohtyp

Method 3: Use the reverse function

Convert the string to a list using the reverse function

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

Result:

moc.batnohtyp

Method 4: Use the collections module method 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'))

Result:

moc.batnohtyp

Method 5: Recursive implementation

#!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'))

Result:

moc.batnohtyp

Method 6: Use the basic Swap operation to exchange symmetrically positioned characters based on the middle

 #!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:      s
trList[i], strList[length-i-1]=strList[length-i-1], strList[i]      i+=1 
 return ''.join(strList) 
print(strReverse('pythontab.com'))

Result:

moc.batnohtyp

##Related free learning recommendations: python video tutorial

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