G :: Computer Transformation
Time Limit: 1 Second Memory Limit: 65536 KB
A sequence consisting of one digit, the number 1 is initially written
into a computer. At each successive time step, the computer
simultaneously tranforms 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 consequitive zeroes will appear in the sequence after n steps?
Input
Every input line contains one natural number n (0 < n <= 1000).
Output
For each input n print the number of consequitive zeroes pairs that will appear in the sequence after n steps.
Sample Input
2 3
Sample Output
1 1Submit