Bobo has a positive-definite matrix
and an
-dimension vector
. He would like to find
where
It can be shown that , which is rational.
Find the value of .
The input consists of several test cases terminated by end-of-file.
The first line of each test case contains an integer n.
The i-th of the following n lines contains n integers.
The last line contains n integers.
*
*
*
*for any
*
* The sum of n does not exceed.
For each test case, print an integer which denotes the result.