HackerRank Python Compile Error Recursion Factorial

Question

Problem

Calculate and print the factorial of a given positive integer. The integer can be as large as 100 .

Here's a link to the problem

My effort

I have tried solutions on other compilers, they are working fine on other compilers, but on hackerrank its not working saying compile time error

# Enter your code here. Read input from STDIN. Print output to STDOUT
def fac(n):
    return 1 if (n < 1) else n * fac(n-1)

no = int(raw_input())
print fac(no)

Any help would be appreciated

Answer 1

This solution works just fine for Python 2 - I ran your code on Hackerrank and it passed all the test cases.

So, the compilation error is shown if the code is compiled with Python 3 .

no = int(raw_input())

NameError: name 'raw_input' is not defined

That's true because raw_input must be replaced with input() in Python 3 .

If the code with the correction is executed afterwards then there's another issue:

print fac(no)

^

SyntaxError: invalid syntax

Again, just add parentheses around fac(no) and then the code compiles and passes all the tests:

So, the full code is below:

def fac(n):
    return 1 if (n < 1) else n * fac(n-1)

no = int(input())
print (fac(no))