Python string-by-character or word-wise reversal method

Purpose

It's interesting to reverse the string literal character or word by phrase.

Method

Look at the character reversal first, the first set the step size of the slice is-1
Copy the Code code as follows:

REVCHARS=ASTRING[::-1]

in [+]: x= ' ABCD '

In [all]: X[::-1]
OUT[66]: ' DCBA '

The second approach is to use reversed (), noting that it returns an iterator that can be used for looping or passing to other "accumulators", not a completed string.
Copy the Code code as follows:

Revchars= '. Join (Reversed (astring))

In []: y=reversed (x)

In [the]: Y
OUT[57]:

in [+]: '. Join (Y)
OUT[58]: ' DCBA '

Then look at the word reversal.

The first approach, create a list, reverse the list, merge with the Join method

Copy the Code code as follows:

in [+]: s= ' Today is really a good day '

In [All]: Rev=s.split ()

In [MAX]: Rev
OUT[40]: [' Today ', ' is ', ' really ', ' a ', ' good ', ' Day ']

in [+]: Rev.reverse ()

In [all]: Rev
OUT[42]: [' Day ', ' good ', ' a ', ' really ', ' is ', ' Today ']

in []: ". Join (REV)
OUT[45]: ' Day good a really is Today '

There is also a line of code to resolve:
Copy the Code code as follows:

Rev= '. Join (S.split () [::-1])

The second approach can be done without changing the original space and using the regular formula:

Copy the Code code as follows:

in [+]: Import re

In [Sat]: Rev=re.split (R ' (\s+) ', s)

in [+]: Rev
OUT[48]: [' Today ', ' ', ' is ', ' ', ' really ', ' ', ' a ', ', ' good ', ' ', ' Day ']

in [+]: Rev.reverse ()

in [+]: Rev
OUT[50]: [' Day ', ' ', ' good ', ' ', ' a ', ' ', ' really ', ', ' is ', ', ' Today ']

In [Wuyi]: rev= '. Join (REV)

In [%]: Rev
OUT[52]: ' Day good a really is Today '

Consider using reversed () instead of poor readability [::-1]
Copy the Code code as follows:

Revwords= '. Join (Reversed (S.split ()))

Revwords= '. Join (Reversed (Re.split (R ' (\s+) ', s)))

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