Competitions

# Domino

Find the number of ways to cover a rectangle 2 × n with domino of size 2 × 1. The coverings that turn themselves into symmetries are considered different.

#### Input

One integer n (0 < n < 65536).

#### Output

Print the number of coverings of rectangle.

Time limit 1 second
Memory limit 128 MiB
Input example #1
1

Output example #1
1

Input example #2
4

Output example #2
5

Author Виталий Бондаренко
Source 1997, X All-Ukrainian Informatics Olympiad