fibonacci_linear.py

"""
Exercise 3

Create a program called fibonacci_linear.py

Requirements

Given a term (n), determine the value of x(n).
In the fibonacci_linear.py program, create a function called fibonnaci. The function should take in an integer and return the value of x(n).
This problem must be solved WITHOUT the use of recursion.
Constraints
n >= 0

Answer below:
"""



n = int(input("Provide a number greater than or equal to 0: "))

def fibonacci(n):
    first_num=0
    second_num=1

    if n>=0:
        for i in range(1,n,1):
            third_num = first_num + second_num
            first_num = second_num
            second_num = third_num
        print(third_num)
    else:
        print("You need to provide a valid input to run the function")


if n>=0 and n<=30:
    fibonacci(n)
else:
    print("You need to provide a valid input to run the function")