How to reverse a string in Python

Reversal method: 1. Use the slicing method to reverse, the syntax is "String[::-1]". 2. First convert the string into a list; then use reverse() to reverse the list elements; finally convert the reversed list into a string. 3. Use the reduce() function, the syntax is "reduce(lambda x,y:y x,string)".

A very boring question encountered in the interview~~~

Requirement: Use as many methods as possible to reverse in the Python environment String, for example, reverse s = "abcdef" to "fedcba"

First method: use string slicing

>>> s="abcdef"
>>> result = s[::-1]
>>> print(result)

Output:

fedcba

th Two: use the reverse method of the list

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

Of course the following will also work

l = list(s)
result = "".join(l[::-1])

The third: use reduce

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

The fourth: use the recursive function

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

The fifth way: using stack

def func(s):
    l = list(s) #模拟全部入栈
    result = ""
    while len(l)>0:
        result += l.pop() #模拟出栈
    return result
result = func(s)

The sixth way: for loop

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

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