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Python: Find the value of the first element in the given list that satisfies the provided testing function

Python List: Exercise - 239 with Solution

Write a Python program to find the value of the first element in the given list that satisfies the provided testing function.

Use a list comprehension and next() to return the first element in lst for which fn returns True.

Sample Solution:

Python Code:

def find(lst, fn):
  return next(x for x in lst if fn(x)) 
print(find([1, 2, 3, 4], lambda n: n % 2 == 1))
print(find([1, 2, 3, 4], lambda n: n % 2 == 0))

Sample Output:

1
2

Flowchart:

Flowchart: Find the value of the first element in the given list that satisfies the provided testing function.

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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