Question

Write (and test) a Python function that rearranges a sequence of integer values so that all the even values appear before all the odd values. Make sure to test all common use-cases (ie, an array with all even numbers, one with all odd numbers, and one with a mixture of odd and even numbers).

What is the running time of your algorithm? Justify your answer.

just not the solution, also need to understand it.
Thanks

Answer 1

Screenshot of the code:

Sample Output:

#Sample Run 1:

#Sample Run 2:

#Sample Run 3:

Code To Copy:

#Run the code in python version 3.x.

#Please indent the code before executing the

#code as per the above screenshot of the code.

#Otherwise, it may give error.

#Define the function to rearrange the

#elements of the list.

def Rearrange(list_arr, n) :

   

    #Define the variables.

    j = -1

    #Begin the for loop.

    #Perform the method of quick sort.

    for i in range(0, n) :

        #If the element at index i is odd then swap it.         

        if (list_arr[i] % 2 == 0) :

            #Increase the value of j by 1.

            j = j + 1

            #Swap the element at i and j index.

            temp_var = list_arr[i]

            list_arr[i] = list_arr[j]

            list_arr[j] = temp_var

#Prompt the user to enter the number of elements of the list.

num = int(input('Enter the number of elements of the list: '))

#Declare the variable.

element_list = []

print('Enter', num, 'elements:')

#Enter the elements.

for _ in range(num):

    ele = int(input())

    element_list.append(ele)

#Call the function to arrange the elements.

Rearrange(element_list, num)

#Display the updated list.

for i in range(0,num) :

    print(element_list[i] ,end= " ")

Running Time of the algorithm:

• The run time of the algorithm is O(n). The loop executes till end of the list, traverse the whole list.
• The n represents the number of elements in the list.