"""
Recursive implementation of the fibonacci sequence
This function should be copied into the Python Tutor. That way you can
see how recursion affects the call stack.
Author: Walker M. White (wmw2)
Date: October 10, 2017 (Python 3 Version)
"""
# Function Definition
def fibonacci(n):
"""
Returns: Fibonacci number a_n
Parameter n: the position to compute
Precondition: n is a nonnegative integer
"""
if n == 0 or n == 1:
return 1
one_back = fibonacci(n-1)
two_back = fibonacci(n-2)
return one_back+two_back
# Function Call
x = fibonacci(5)