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Python: Create a deque and append few elements to the left and right, then remove some elements from the left, right sides and reverse the deque

Python Collections: Exercise-7 with Solution

Write a Python program to create a deque and append few elements to the left and right, then remove some elements from the left, right sides and reverse the deque.

Sample Solution:

Python Code:

import collections
# Create a deque
deque_colors = collections.deque(["Red","Green","White"])
print(deque_colors)
# Append to the left
print("\nAdding to the left: ")
deque_colors.appendleft("Pink")
print(deque_colors)
# Append to the right
print("\nAdding to the right: ")
deque_colors.append("Orange")
print(deque_colors)
# Remove from the right
print("\nRemoving from the right: ")
deque_colors.pop()
print(deque_colors)
# Remove from the left
print("\nRemoving from the left: ")
deque_colors.popleft()
print(deque_colors)
# Reverse the dequeue
print("\nReversing the deque: ")
deque_colors.reverse()
print(deque_colors)

Sample Output:

deque(['Red', 'Green', 'White'])

Adding to the left: 
deque(['Pink', 'Red', 'Green', 'White'])

Adding to the right: 
deque(['Pink', 'Red', 'Green', 'White', 'Orange'])

Removing from the right: 
deque(['Pink', 'Red', 'Green', 'White'])

Removing from the left: 
deque(['Red', 'Green', 'White'])

Reversing the deque: 
deque(['White', 'Green', 'Red'])

Flowchart:

Python Collections: Create a deque and append few elements to the left and right, then remove some elements from the left, right sides and reverse the deque.

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Python Code Editor:

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Previous: Write a Python program that accepts number of subjects, subject names and marks. Input number of subjects and then subject name, marks separated by a space in next line. Print subject name and marks in order of its first occurrence.
Next: Write a Python program to create a deque from an existing iterable object.

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Python: Tips of the Day

Use Reversed() In for Loops:

>>> tasks = ['laundry', 'picking up kids', 'gardening', 'cooking']
>>> for task in reversed(tasks):
...     print(task)
... 
cooking
gardening
picking up kids
laundry