Python: Check if a given function returns True for at least one element in the list

Last update on December 21 2024 13:10:46 (UTC/GMT +8 hours)

Check Any True in List

Write a Python program to check if a given function returns True for at least one element in the list.

Use all() and fn to check if fn returns False for all the elements in the list.

Sample Solution:

Python Code:

# Define a function named 'test' that checks whether a condition is False for all elements in a list.
def test(lst, fn=lambda x: x):
    return all(not fn(x) for x in lst)
    # The 'all' function checks if the given condition 'not fn(x)' is False for all elements in the list 'lst'.

# Test the 'test' function with different lists and conditions.
print(test([1, 0, 2, 3], lambda x: x >= 3))
# Check if all elements are less than 3. (Expected output: False)

print(test([1, 0, 2, 3], lambda x: x < 0))
# Check if all elements are less than 0. (Expected output: False)

print(test([2, 2, 4, 4]))
# Check if all elements are False (considering default condition of 'x').
# Since there are no False elements, the expected output is True.

Sample Output:

False
True
False

Flowchart:

Python Code Editor:

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