L ists 199 15 25 35 45 55 id of list after function

L
ISTS
199
[15, 25, 35, 45, 55]
ID of list after function call: 65565640
The list after the function call:
[10, 20, 30, 40, 50]
9.8 L
IST
M
ANIPULATION
In this chapter, we have learnt to create a list and the
different ways to manipulate lists. In the following
programs, we will apply the various list manipulation
methods.
Program 9-3 Write a menu driven program to perform
various list operations, such as:
• Append an element
• Insert an element
• Append a list to the given list
• Modify an existing element
• Delete an existing element from its position
• Delete an existing element with a given value
• Sort the list in ascending order
• Sort the list in descending order
• Display the list.
#Program 9-3
#Menu driven program to do various list operations
myList = [22,4,16,38,13] #myList already has 5 elements
choice = 0
while True:
print("The list 'myList' has the following elements", myList)
print("\nL I S T O P E R A T I O N S")
print(" 1. Append an element")
print(" 2. Insert an element at the desired position")
print(" 3. Append a list to the given list")
print(" 4. Modify an existing element")
print(" 5. Delete an existing element by its position")
print(" 6. Delete an existing element by its value")
print(" 7. Sort the list in ascending order")
print(" 8. Sort the list in descending order")
print(" 9. Display the list")
print(" 10. Exit")
choice = int(input("ENTER YOUR CHOICE (1-10): "))
#append element
if choice == 1:
element = int(input("Enter the element to be appended: "))
myList.append(element)
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C
OMPUTER
S
CIENCE
– C
LASS XI
200
print("The element has been appended\n")
#insert an element at desired position
elif choice == 2:
element = int(input("Enter the element to be inserted: "))
pos = int(input("Enter the position:"))
myList.insert(pos,element)
print("The element has been inserted\n")
#append a list to the given list
elif choice == 3:
newList = int(input("Enter the list to be appended: "))
myList.extend(newList)
print("The list has been appended\n")
#modify an existing element
elif choice == 4:
i = int(input("Enter the position of the element to be
modified: "))
if i < len(myList):
newElement = int(input("Enter the new element: "))
oldElement = myList[i]
myList[i] = newElement
print("The element",oldElement,"has been modified\n")
else:
print("Position of the element is more than the length
of list")
#delete an existing element by position
elif choice == 5:
i = int(input("Enter the position of the element to be
deleted: "))
if i < len(myList):
element = myList.pop(i)
print("The element",element,"has been deleted\n")
else:
print("\nPosition of the element is more than the length
of list")
#delete an existing element by value
elif choice == 6:
element = int(input("\nEnter the element to be deleted: "))
if element in myList:
myList.remove(element)
print("\nThe element",element,"has been deleted\n")
else:
print("\nElement",element,"is not present in the list")
#list in sorted order
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ISTS
201
elif choice == 7:
myList.sort()
print("\nThe list has been sorted")
#list in reverse sorted order
elif choice == 8:
myList.sort(reverse = True)
print("\nThe list has been sorted in reverse order")
#display the list
elif choice == 9:
print("\nThe list is:", myList)
#exit from the menu
elif choice == 10:
break
else: