HackerRank - Map and Lambda Function Solution
Let's learn some new Python concepts! You have to generate a list of the first N fibonacci numbers, 0 being the first number. Then, apply the map function and a lambda expression to cube each fibonacci number and print the list.
map() function applies a function to every member of an iterable and returns the result. It takes two parameters: first, the function that is to be applied and secondly, the iterables.
Let's say you are given a list of names, and you have to print a list that contains the length of each name.
>> print (list(map(len, ['Tina', 'Raj', 'Tom']))) [4, 3, 3]
Lambda is a single expression anonymous function often used as an inline function. In simple words, it is a function that has only one line in its body. It proves very handy in functional and GUI programming.
>> sum = lambda a, b, c: a + b + c >> sum(1, 2, 3) 6
Lambda functions cannot use the return statement and can only have a single expression. Unlike def, which creates a function and assigns it a name, lambda creates a function and returns the function itself. Lambda can be used inside lists and dictionaries.
One line of input: an integer N.
A list on a single line containing the cubes of the first N fibonacci numbers.
[0, 1, 1, 8, 27]
The first fibonacci numbers are [0, 1, 1, 2, 3], and their cubes are [0, 1, 1, 8, 27].
Solution in Python3
cube = lambda x: x**3 def fibonacci(n): if n<2: return range(n) init = [0,1] for i in range(0,n-2): add =init[i+1]+init[i] init.append(add) return(init) if __name__ == '__main__': n = int(input()) print(list(map(cube, fibonacci(n))))