How to Reverse a String in Python Using a for Loop
In Python, you can reverse a string using a for loop. The syntax is as follows:string_to_reverse = string to reversefor i in range 0, ...

In Python, you can reverse a string using a for loop. The syntax is as follows:
string_to_reverse = "string to reverse"
for i in range(0, len(string_to_reverse)):
string_to_reverse[i], string_to_reverse[i+1] = string_to_reverse[i], string_to_reverse[i+1]
This code will reverse the string "string to reverse" and return the new string.
- Using a loop, reverse a string in Python.
- In Python, use recursion to reverse a string.
- Python stack-based string reversal
- In Python, use an extended slice to reverse a string.
- In Python, use the reversed() method to reverse a string.
- In Python, use list comprehension() to reverse a string.
- In Python, use the function call to reverse a string.
- In Python, how do you reverse a specific string?
- In Python, how do you reverse a string without using the reverse function?
Here's my attempt, which makes use of a decorator and a for loop. Put everything in one file.
Implementation details:
def reverse(func):
def reverse_engine(items):
partial_items = []
for item in items:
partial_items = [item] + partial_items
return func(partial_items)
return reverse_engine
Usage:
Example 1:
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
Example 2:
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
Example 3:
@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
Because the Python string library does not have an in-built "reverse()" function like other Python containers like list, knowing other methods to reverse string can be useful. This article discusses several approaches in Python.
Example:
Input: Geeksforgeeks Output: skeegrofskeeG
Using a loop, reverse a string in Python.
In this example, we use a function to reverse a string, which iterates through each element and intelligently joins each character at the start to produce the reversed string.
Time complexity: O(n)
Auxiliary Space: O(1)
Implementation:
Python3
@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
36 @reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
37The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG1
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG3
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG5
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG6
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG7
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG8
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG9
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG1
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG6
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
83 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG1
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
86 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG1
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
89The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
61@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
64@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
65@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
66The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
68@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
50@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
64@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
54@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
66The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
68@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
59Output
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG
In Python, use recursion to reverse a string.
To reverse the string, the string is passed as an argument to a recursive function. The function's base condition is that the string is returned if its length is equal to zero. If not equal to 0, the reverse function is called recursively to slice the string except for the first character and concatenate the first character to the end of the sliced string. ‘
Time complexity: O(n)
Auxiliary Space: O(n)
Implementation:
Python3
@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
36 @reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
37The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
Input: Geeksforgeeks Output: skeegrofskeeG73
Input: Geeksforgeeks Output: skeegrofskeeG74
@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
50The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
Input: Geeksforgeeks Output: skeegrofskeeG78
Input: Geeksforgeeks Output: skeegrofskeeG79
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG9
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
86 @reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
89The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG84
Input: Geeksforgeeks Output: skeegrofskeeG79
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG9
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
86 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG88
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG89
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG80
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
83 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG82
Input: Geeksforgeeks Output: skeegrofskeeG78
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG84
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
89The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
61@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
64@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
65@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
66The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
68@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
50@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
64@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
372@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
66The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
68@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
59Output
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
8Python stack-based string reversal
An empty stack is created. The string is pushed to the stack one character at a time. All characters from the stack are popped one by one and returned to a string.
Time complexity: O(n)
Auxiliary Space: O(n)
Implementation:
Python3
@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
378@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
379@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
36 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG01
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG03
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG05
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
86 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG03
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG10
@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
36 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG12
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
86 Input: Geeksforgeeks Output: skeegrofskeeG74
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG16
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG18
@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
36 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG20
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
Input: Geeksforgeeks Output: skeegrofskeeG73
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG23
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
Input: Geeksforgeeks Output: skeegrofskeeG78
Input: Geeksforgeeks Output: skeegrofskeeG79
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG9
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
86 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG30
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG32
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG33
@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
36 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG35
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG37
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG39
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG40
@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
36 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG42
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
Input: Geeksforgeeks Output: skeegrofskeeG73
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG20
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG9
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
86The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
86 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG50
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG52
@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
36 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG54
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG56
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
Input: Geeksforgeeks Output: skeegrofskeeG74
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG59
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG62
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG03
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG66
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG69
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG5
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG6
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG7
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG74
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
64Input: Geeksforgeeks Output: skeegrofskeeG78
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG77
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG89
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG79
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG9
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG81
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG84
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG86
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG88
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG3
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG93
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG95
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG5
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG6
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG7
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG74
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
64Input: Geeksforgeeks Output: skeegrofskeeG78
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG77
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG89
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG79
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG9
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG88
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
83The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
810@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
86 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG88
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
817@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
89The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
61@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
64@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
65@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
66The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
68@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
50@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
64@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
831@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
66The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
68@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
59Output
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
6In Python, use an extended slice to reverse a string.
Extended slice allows you to put a "step" field as [start, stop, step], and giving no field as start and stop indicate the default values of 0 and string length, respectively, and "-1" denotes starting from the end and stopping at the beginning, thus reversing a string.
Time complexity: O(n)
Auxiliary Space: O(1)
Implementation:
Python3
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
837@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
36 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG54
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG88
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
843@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
844The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG89
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG84
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
86 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG88
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
89The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
61@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
64@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
65@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
66The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
68@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
50@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
64@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
866@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
66The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
68@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
59Output
@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
5In Python, use the reversed() method to reverse a string.
The reversed() function returns the reversed iterator of the given string, and its elements are then joined using join() to form an empty string. And a reversed order string is created.
Time complexity: O(n)
Auxiliary Space: O(1)
Implementation:
Python3
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
872@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
873@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
837@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
36 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG54
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG88
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
881@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
882@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
883The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
86 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG88
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
89The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
61@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
64@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
65@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
66The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
68@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
50@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
64@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
603@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
66The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
68@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
59Output
Input: Geeksforgeeks Output: skeegrofskeeG7
In Python, use list comprehension() to reverse a string.
List comprehension generates a list of a string's elements in reverse order, which is then joined using join(). And a reversed order string is created.
Time complexity: O(n)
Auxiliary Space: O(1)
Implementation:
Python3
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
837@reverse
def reverse_and_square(numbers):
return list(
map(lambda number: number ** 2, numbers)
)
reverse_and_square(range(1, 6))
# [25, 16, 9, 4, 1]
36 The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG54
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG88
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
615The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG5
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG6
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG7
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG74
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
64Input: Geeksforgeeks Output: skeegrofskeeG74
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG59
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
844The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG89
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
625@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
844The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG89
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
625@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
844The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG89
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
631The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG0
@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
86 @reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
634@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
89The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG2
@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
61@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
64@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
642@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
643@reverse
def echo_alphabets(word):
return ''.join(word)
echo_alphabets('hello')
# olleh
88 @reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
63@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
64@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
603@reverse
def echo_words(words):
return words
echo_words([':)', '3.6.0', 'Python', 'Hello'])
# ['Hello', 'Python', '3.6.0', ':)']
648Output
The original string is : Geeksforgeeks The reversed string(using loops) is : skeegrofskeeG8
In Python, use the function call to reverse a string.
Function for reversing a string by converting it from string to list, then back to string.