Orz panda emotion is a famous emotion in XDU/ACM-ICPC QQ groups.
Big Big Xi loves to create new Orz panda emotions.
Now he has a matrix with n lines and m columns,form n*m cells.
And he wants to insert some small Orz pandas to this matrix to create a big emotion.
In each cell of the matrix,he will determine whether put a small Orz panda or not.
For some reasons,he has some special needs of the emotions:
1.In the ith column,there must be a[i] small Orz pandas. (1<=i<=m)
2.In the ith line,assume the total number of Orz pandas is x, x mod 2 must be b[i]. (1<=i<=n)
For example, if n=2 and m=3,a[1..3]={1,1,1},b[1..2]={1,0}
An adapted answer can be like this:
Now, Big Big Xi wants to know there are how many adapted ways to insert the pandas.