Fibonacci Numbers

Time Limit: 1 Second    Memory Limit: 32768 KB

A Fibonacci sequence is calculated by adding the previous two members of the sequence, with the first two members being both 1.

f(1) = 1, f(2) = 1, f(n > 2) = f(n - 1) + f(n - 2)

Input

Your task is to take a number as input.

Output

Print that Fibonacci number.

Sample Input

100

Sample Output

354224848179261915075

Submit

Source: University of Waterloo Local Contest 1996.10.05