Reverse each element of an array then sort the array in Python

By | September 30, 2023

Given an array arr1[] of size n, so firstly we have to reverse each element of an array, and store each of that reversed element in new arr2[] and then sort.

Examples:

Input : arr1[]={45,67,98,10}
Output : after sorting=>{1,54,76,89}
Explanation :
arr1[]={45,67,98,10}

so after reversing each element:
arr2[]={54,76,89,1}

after sorting arr2[] becomes:
arr2={1,54,76,89}

Input : arr1[]={20,56,90,19,42,67}
Output : after sorting=>{2,9,24,65,76,91}

Approach:

  1. After taking the input just start a for loop in which we are reversing each element of arr1[] and store that in arr2[].
  2. After reversing and storing all the reverse elements in arr2[], then we have to sort arr2[].
  3. Then just print arr2[].

Below is the implementation:

# Python program to reverse each element of a list
# after reversing and storing in a new array
# sort the new array

# Function to reverse each element and sort the list
def reverse_sort(arr1, n):
    arr2 = []

    for i in range(n):
        # Convert the element to a string
        arr1[i] = str(arr1[i])
        # Reverse the string
        j = arr1[i][::-1]
        # After reversing, convert it back to an integer
        arr2.append(int(j))

    # Sort the list in ascending order
    arr2.sort()
    return arr2

# Driver Code
if __name__ == "__main__":
    arr1 = list(map(int, input().split()))
    l_sort = reverse_sort(arr1, len(arr1))
    for i in l_sort:
        print(i, end=" ")

Input:

20 56 90 19 42 67

Output:

2 9 24 65 76 91

Time Complexity: O(n logn)
Space Complexity: O(n)

Please write comments if you find anything incorrect. A gentle request to share this topic on your social media profile.

Author: Mithlesh Upadhyay

Mithlesh Upadhyay is a Computer Science and AI expert from Madhya Pradesh with strong academic background (BE in CSE and M.Tech in AI) and over six years of experience in technical content development. He has contributed tech articles, led teams, and worked in Full Stack Development and Data Science. He founded the w3colleges.org portal for learning resources.