Pierre is famous for his macarons. He makes round macarons, stored in square boxes of size , and
oval-shaped macarons, stored in rectangular boxes of size
(or, rotated, in rectangular boxes of
size
). For the purpose of a buffet, Pierre wishes to tile a rectangular table of size
with the
two kinds of macarons, meaning that the table must be completely full, with no empty space left. The
width
of the table is small, for the guest to be able to grab the macarons easily, and the length
of
the table is large, to accommodate a huge number of guests. To keep the table pretty, the orientation of
macarons should always be aligned with the sides of the table.
Pierre wishes to know how many ways there are to tile the table. Can you help him?
Input Specification
The input consists of the following integers:
- the value of
, an integer, on the first line;
- the value of
, an integer, on the second line.
Constraints
The input satisfies and
.
Output Specification
The output should consist of the total number of tilings, given modulo , on a single line.
Sample Input 1
2
2
Sample Output 1
7
Sample Input 2
2
4
Sample Output 2
71
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