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Python: Find the indexes of all None items in a given list

Python List: Exercise - 202 with Solution

Write a Python program to find the indexes of all None items in a given list.

Sample Solution:

Python Code:

def relative_order(lst):
    result = [i for i in range(len(lst)) if lst[i] == None]
    return result

nums = [1, None, 5, 4,None, 0, None, None]
print("Original list:")
print(nums)
print("\nIndexes of all None items of the list:")
print(relative_order(nums))

Sample Output:

Original list:
[1, None, 5, 4, None, 0, None, None]

Indexes of all None items of the list:
[1, 4, 6, 7]

Pictorial Presentation:

Python List: Find the indexes of all None items in a given list.

Flowchart:

Flowchart: Find the indexes of all None items in a given list.

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Python: Tips of the Day

Floor Division:

When we speak of division we normally mean (/) float division operator, this will give a precise result in float format with decimals.

For a rounded integer result there is (//) floor division operator in Python. Floor division will only give integer results that are round numbers.

print(1000 // 300)
print(1000 / 300)

Output:

3
3.3333333333333335