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Python: Check if a given function returns True for every element in a list

Python List: Exercise - 243 with Solution

Write a Python program to check if a given function returns True for every element in a list.

Use all() in combination with map() and fn to check if fn returns True for all elements in the list.

Sample Solution:

Python Code:

def every(lst, fn = lambda x: x):
  return all(map(fn, lst))
print(every([4, 2, 3], lambda x: x > 1))
print(every([4, 2, 3], lambda x: x < 1))
print(every([4, 2, 3], lambda x: x == 1))

Sample Output:

True
False
False

Flowchart:

Flowchart: Check if a given function returns True for every element in a 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