IWGBS - 0110SS


Dor is IWGolymp student so he has to count in how many ways he can make N digit numbers that is formed by ones and zeroes. But zeroes can not be next to each other. Help to him in how many different numbers can he make.

For example, N = 3: 101, 010, 111, 110, 011

Note: A leading zero is allowed.

Input

A positive integer N (1 <= N <= 10000).

Output

Answer for the problem.

Example

Input:
2

Output:
3

hide comments
RAJDEEP GUPTA: 2012-02-21 17:39:02

I assumed that the answer is at most 2100 digits long.

krabathor: 2012-02-20 21:55:56

should be moved to tutorial

Devil D: 2012-02-16 14:57:32

U need to implement Big Int for this

Azat Taryhchiyev: 2012-02-16 14:43:50

No it's a long arithmethic problem

Aman Kumar: 2012-02-16 14:26:05

answer duznt fit int long long...

Aman Kumar: 2012-02-16 14:08:16

does the answer fit in long long....??


Added by:Azat Taryhchiyev
Date:2012-02-16
Time limit:0.100s-3.085s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ASM64