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

Python List: Exercise - 229 with Solution

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

Use a list comprehension, enumerate() and next() to return the index of the first element in nums for which fn returns True.

Sample Solution:

Python Code:

def find_index(nums, fn):
  return next(i for i, x in enumerate(nums) if fn(x))
print(find_index([1, 2, 3, 4], lambda n: n % 2 == 1))

Sample Output:

0

Flowchart:

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

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Previous: Write a Python program to get every element that exists in any of the two given lists once, after applying the provided function to each element of both.
Next: Write a Python program to find the indexes of all elements in the given list that satisfy the provided testing function.

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Python: Tips of the Day

Big Number Readability:

you can separate zeros with underscore (_)

print(2_000_000)
print(2_000_000 +1)

Output:

2000000
2000001