How to Rotate a Python List Left or Right?

Python List Rotation

Introduction:
Rotating a Python list involves shifting its elements either left or right by a specified number of positions.

Method 1:
Question: How to rotate a list to the left?
Answer:

<code class="python">def rotate_left(l, n):
    return l[n:] + l[:n]</code>

Example:

<code class="python">example_list = [1, 2, 3, 4, 5]
result = rotate_left(example_list, 2)
print(result)  # Output: [3, 4, 5, 1, 2]</code>

Method 2:
Question: How to rotate a list to the right?
Answer:

<code class="python">def rotate_right(l, n):
    return l[-n:] + l[:-n]</code>

Example:

<code class="python">example_list = [1, 2, 3, 4, 5]
result = rotate_right(example_list, 2)
print(result)  # Output: [4, 5, 1, 2, 3]</code>

Explanation:
Both methods use slicing to create new lists:

• Left Rotation: The l[n:] slice includes elements from the nth position to the end, while l[:n] includes elements from the beginning to the nth position.
• Right Rotation: The l[-n:] slice includes elements from the last n positions of the list, while l[:-n] includes elements from the beginning to the second-to-last nth position.

The resulting shifted list is then formed by concatenating these slices.

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