There is a grid with $H$ horizontal rows and $W$ vertical columns. Let $(i,j)$ denote the square at the $i$-th row from the top and the $j$-th column from the left.

For each $i$ and $j$ $(1\le i\le H,1\le j\le W)$. Square $(i,j)$ is described by a character $a_{i,j}$. If $a_{i,j}$is ., square $(i,j)$ is an empty square; if $a_{i,j}$ is #, square $(i,j)$ is a wall square. It is guaranteed that squares $(1,1)$ and $(H,W)$ are empty squares.

Taro will start from square $(1,1)$ and reach $(H,W)$ by repeatedly moving right or down to an adjacent empty square.

Find the number of Taro's paths from square $(1,1)$ to $(H,W)$. As the answer can be extremely large, find the count modulo ${10}^9+7$.

Constraints

• $H$ and $W$ are integers
• $2\le H,W\le 1000$
• $a_{i,j}$ is . or #
• Squares $(1,1)$ and $(H,W)$ are empty squares

Input Specification

The first line will contain 2 space separated integers, $H$ and $W$.

The next $H$ lines will each contain $W$ characters, either a . or #.

Output Specification

Print the number of Taro's paths from square $(1,1)$ to $(H,W)$, modulo ${10}^9+7$.

Sample Input 1

3 4
...#
.#..
....

Sample Output 1

3

Explanation For Sample 1

There are three paths as follows:

Sample Input 2

5 2
..
#.
..
.#
..

Sample Output 2

0

Explanation For Sample 2

There may be no paths.

Sample Input 3

5 5
..#..
.....
#...#
.....
..#..

Sample Output 3

24

Sample Input 4

20 20
....................
....................
....................
....................
....................
....................
....................
....................
....................
....................
....................
....................
....................
....................
....................
....................
....................
....................
....................
....................

Sample Output 4

345263555

Explanation For Sample 4

Be sure to print the count modulo ${10}^9+7$.