Python program to swap any two elements in the list

Method 1: Simply swap values using comma separator

We will swap the elements directly using the common swapping method.

Syntax:

a, b = b, a

Program to swap any two elements in the list

# Python program to swap element of a list

# Getting list from user
myList = []
length = int(input("Enter number of elements: "))
for i in range(0, length):
    val = int(input())
    myList.append(val)

print("Enter indexes to be swapped ")
index1 = int(input("index 1: "))
index2 = int(input("index 2: "))

print("Initial List: ", myList)
# Swapping given elements
myList[index1], myList[index2] = myList[index2], myList[index1]

# Printing list 
print("List after Swapping: ", myList)

Output:

Enter number of elements: 5
10
20
30
40
50
Enter indexes to be swapped
index 1: 2
index 2: 4
Initial List:  [10, 20, 30, 40, 50]
List after Swapping:  [10, 20, 50, 40, 30]

Method 2: Pop values and then inserting them back

One more method to swap values is to pop out values at a given index and then insert them back to the given index.

Algorithm :

• Get list and index values from the user.
• Swap values using pop and insert method.
  • val1 = pop(index1)
  • val2 = pop(index2 - 1)
  • insert(index1, val2)
  • insert(index2, val1)
• Print the list.

Program to swap any two elements in the list

# Python program to swap element of a list

# Getting list from user
myList = []

length = int(input("Enter number of elements  "))
for i in range(0, length):
    val = int(input())
    myList.append(val)

print("Enter indexes to be swapped ")
index1 = int(input("index 1: "))
index2 = int(input("index 2: "))

print("Initial List: ", myList)
# Swapping given element
val1 = myList.pop(index1)
val2 = myList.pop(index2 - 1)
myList.insert(index1, val2)
myList.insert(index2, val1)

# Printing list 
print("List after Swapping: ", myList)

Output:

Enter number of elements  5
10
20
30
40
50
Enter indexes to be swapped
index 1: 1
index 2: 4
Initial List:  [10, 20, 30, 40, 50]
List after Swapping:  [10, 50, 30, 40, 20]

Swapping two values based on their values entered by the user

# Python program to swap element of a list

# Getting list from user
myList = []
length = int(input("Enter number of elements: "))
for i in range(0, length):
    val = int(input())
    myList.append(val)

print("Enter values to be swapped ")
value1 = int(input("value 1: "))
value2 = int(input("value 2: "))

index1 = myList.index(value1)
index2 = myList.index(value2)

print("Initial List: ", myList)

# Swapping given element
myList[index1], myList[index2] = myList[index2], myList[index1]

# Printing list 
print("List after Swapping: ", myList)

Output:

Enter number of elements: 5
10
20
30
40
50
Enter values to be swapped
value 1: 10
value 2: 50
Initial List:  [10, 20, 30, 40, 50]
List after Swapping:  [50, 20, 30, 40, 10]