Hackerrank Built-in Functions and Lambdas 4

Question 1

What is the output of `(lambda a, b: a if a > b else b)(10, 20)`?

Accepted Answer

20

Answer

The lambda returns the larger of a and b; since 20 > 10, it returns 20.

Question 2

What does `list(map(str, [1, 2, 3]))` return?

Accepted Answer

['1', '2', '3']

Answer

map applies str() to each integer, producing a list of string representations.

Question 3

What does `bool(0)` return?

Accepted Answer

False

Answer

bool() converts 0 to False because 0 is falsy in Python.

Question 4

Which expression using `reduce` from functools computes the product of [1,2,3,4]?

Accepted Answer

reduce(lambda x, y: x * y, [1,2,3,4])

Answer

reduce applies the multiplication lambda cumulatively: 1*2*3*4 = 24.

Question 5

What does `type(lambda x: x)` return?

Accepted Answer

Answer

A lambda expression creates an anonymous function object, so its type is 'function'.

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