M00PAIR - 0 0 Pairs

A sequence consisting of one digit, the number 1 is initially written into a computer. At each successive time step, the computer simultaneously transforms each digit 0 into the sequence 1 0 and each digit 1 into the sequence 0 1.

So, after the first time step, the sequence 0 1 is obtained; after the second, the sequence 1 0 0 1, after the third, the sequence 0 1 1 0 1 0 0 1 and so on.

How many pairs of consecutive zeroes will appear in the sequence after n steps?

Input

Clarification for this Problem: The Range of inputs is from 1 to 999 in some order and in particular not in ascending order

Output

For each input n print the number of consecutive zeroes pairs that will appear in the sequence after n steps.

Sample

Sample Input 
1
2
3
4
5
Sample output
0
1
1
3
5

Notice : Long output - 1.45MB - there are a lot of input/output so it is easy to TLE if you don't optimize in/out if you use Java ...


Added by:psetter
Date:2009-02-27
Time limit:1s
Source limit:20000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ERL JS-RHINO NODEJS PERL6 VB.NET
Resource:Southeastern European 2005

hide comments
2023-12-17 16:53:28
Same feeling as sw2022.
(It => It's)
2023-09-06 06:32:50
It too hard in C++ without high-precision multiplication..,why not ask for modulo answer?

Last edit: 2023-09-06 06:34:54
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