Package for this problem was not updated by the problem writer or Codeforces administration after we’ve upgraded the judging servers. To adjust the time limit constraint, solution execution time will be multiplied by 2. For example, if your solution works for 400 ms on judging servers, then value 800 ms will be displayed and used to determine the verdict.

The following languages are only available languages for the problems from the contest

Unknown Language Round #2:

- Io-2008-01-07 (Win32)

Virtual contest is a way to take part in past contest, as close as possible to participation on time. It is supported only ICPC mode for virtual contests.
If you've seen these problems, a virtual contest is not for you - solve these problems in the archive.
If you just want to solve some problem from a contest, a virtual contest is not for you - solve this problem in the archive.
Never use someone else's code, read the tutorials or communicate with other person during a virtual contest.

No tag edit access

The problem statement has recently been changed. View the changes.

×
G. Fibonacci army

time limit per test

2 secondsmemory limit per test

256 megabytesinput

standard inputoutput

standard outputKing Cambyses loves Fibonacci numbers. He has several armies. Today he wants to make a new army for himself and he wants the number of men in this army to be the *n*-th Fibonacci number.

Given *n* you should find *n*-th Fibonacci number. The set of Fibonacci numbers start with *f*_{0} = *f*_{1} = 1 and for each *i* ≥ 2, *f*_{i} = *f*_{i - 1} + *f*_{i - 2}.

Input

Input contains a single integer *n* (1 ≤ *n* ≤ 20).

Output

Write a single integer. The *n*-th Fibonacci number.

Examples

Input

2

Output

2

Input

1

Output

1

Codeforces (c) Copyright 2010-2021 Mike Mirzayanov

The only programming contests Web 2.0 platform

Server time: May/13/2021 09:04:45 (h2).

Desktop version, switch to mobile version.

Supported by

User lists

Name |
---|