HackerRank Map and Lambda Function solution in Python

HackerRank Map and Lambda Function solution in Python – In this Map and Lambda Function problem in Python programming, 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.

Concept

The 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

Note:

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.

HackerRank Map and Lambda function problem solution in Python 2.

# Enter your code here. Read input from STDIN. Print output to STDOUT
def fib(n):
	if n == 0:
		return 0
	if n == 1:
		return 1
	return fib(n-2) + fib(n-1)
n = int(raw_input())
cube = lambda x: x*x*x
print list(map(cube,[fib(a) for a in xrange(n)]))

Map and Lambda function problem solution in Python 3.

cube = lambda x: pow(x,3)# complete the lambda function 
def fibonacci(n):
    # return a list of fibonacci numbers
    lis = [0,1]
    for i in range(2,n):
        lis.append(lis[i-2] + lis[i-1])
    return(lis[0:n])

Problem solution in pypy programming.

cube = lambda x: x**3

def fibonacci(n):
    # return a list of fibonacci numbers
    result = [0,1]
    for i in range(2,n):
        result.append(result[i-1]+result[i-2])
        
    return result[:n]

Problem solution in pypy3 programming.

cube = lambda x: pow(x,3)# complete the lambda function 

def fibonacci(n):
    # return a list of fibonacci numbers
    lis = [0,1]
    
    for i in range(2,n):
        lis.append(lis[i-2] + lis[i-1])
        
    return(lis[0:n])