33 lines
490 B
Markdown
33 lines
490 B
Markdown
|
Your library teacher has a 2-row bookshelf that can contain N books in each row. She wants to know the number of ways that she can fill the bookshelf with red-colored books and blue-colored books such that no 2 red-colored books are adjacent to each other (horizontally or vertically).
|
||
|
|
|
||
|
|
Input: the integer, N
|
||
|
|
Output: the number of ways you can place red-colored books and blue-colored books onto the bookshelf
|
||
|
|
|
||
|
|
Ex: N=3
|
||
|
|
|
||
|
|
|
||
|
|
Input: 3
|
||
|
|
|
||
|
|
BB
|
||
|
|
BB
|
||
|
|
|
||
|
|
BB
|
||
|
|
BR
|
||
|
|
|
||
|
|
BR
|
||
|
|
BB
|
||
|
|
|
||
|
|
RB
|
||
|
|
BB
|
||
|
|
|
||
|
|
BB
|
||
|
|
RB
|
||
|
|
|
||
|
|
RB
|
||
|
|
BR
|
||
|
|
|
||
|
|
BR
|
||
|
|
RB
|
||
|
|
|
||
|
|
Output: 6
|