Challenge 5: Compute nth Fibonacci Number

Problem Statement

Implement the Fibonacci function that takes a number n and calculates the nth Fibonacci.

The Fibonacci Sequence is the series of numbers: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, … The next number is found by adding up the previous two consecutive numbers.

Input

An integer

Output

nth fibonacci term

Sample Input

7

Sample Output

13

Coding Exercise

Write your code in the code widget below. If you don’t get it right, don’t fret; the solution is also given.