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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 Code Editor:

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Python: Tips of the Day

Chunks a list into smaller lists of a specified size:

Example:

from math import ceil

def tips_chunk(lst, size):
  return list(
    map(lambda x: lst[x * size:x * size + size],
      list(range(0, ceil(len(lst) / size)))))

print(tips_chunk([1, 2, 3, 4, 5, 6], 3))

Output:

[[1, 2, 3], [4, 5, 6]]