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
prasoonbatham: 2017-01-16 18:19:02

Iterative dp + BigInteger in Java :)

vengatesh15: 2016-12-31 10:45:06

Thanks for the problem learnt how to use BIGINT

ndv17: 2016-08-22 10:42:11

:D

mkfeuhrer: 2016-07-11 21:06:47

easy in python if u get the dp relation!

arthur: 2016-03-12 12:21:48

I have seen more tougher dp problems.

SHIVEK SACKLECHA: 2015-12-26 07:49:40

My 50th problem :)

Mayank Garg: 2015-11-05 19:59:29

Easy one but in java ;)

Shubham Jain: 2015-08-14 09:43:31

my 100 :) an easy task with BigInteger

monish007: 2015-07-06 16:27:35

1 day + 55 line in c++ = AC in one go!!!

:.Mohib.:: 2015-06-11 15:33:23

5 lines in python ;)
Solved in c :)

Last edit: 2015-06-11 16:15:28

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