题目描述
Problem Description
lxhgww's nickname is "Little L" because he loves L-shaped objects.
Little L's living room is a rectangular area of size $r \times c$. He wants to cover the entire living room with L-shaped floor tiles. Some positions in the living room have pillars and cannot be covered with tiles.
Little L wants to know how many different ways there are to cover the entire living room with L-shaped tiles.
It should be noted that, as shown in the figure below, the lengths of the two ends of the L-shaped tile can vary, but they cannot be zero.

After the installation, all areas without pillars in the living room must be covered with tiles, and the same area cannot be covered multiple times.
Input Format
The first line of input contains two integers, $r$ and $c$, representing the size of the living room.
Following are $r$ lines, each containing $c$ characters. The characters can be either _ or *. _ indicates an empty position that must be covered with a tile, and * indicates a position with a pillar that cannot be covered.
Output Format
Output a single line containing an integer, which represents the number of ways to cover the entire living room. Since this number may be very large, output the remainder of this number divided by $20110520$.
Sample Input and Output
Sample Input #1
2 2
*_
__
Sample Output #1
1
Sample Input #2
3 3
___
_*_
___
Sample Output #2
8
Notes
Data Size and Constraints
| Test Case Number | Data Constraints |
|---|---|
| $1 \sim 2$ | $1 \le r \times c \le 25$ |
| $3 \sim 5$ | $1 \le r \times c \le 100$ and ($r = 2$ or $c = 2$) |
| $6 \sim 10$ | $1 \le r \times c \le 100$ |
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分