5432：Pyramid Split

Xiao Ming is a citizen who's good at playing,he has lot's of gold cones which have square undersides,let's call them pyramids.

Anyone of them can be defined by the square's length and the height,called them width and height.

To easily understand,all the units are mile.Now Ming has $n$ pyramids,there height and width are known,Xiao Ming wants to make them again to get two objects with the same volume.

Of course he won't simply melt his pyramids and distribute to two parts.He has a sword named "Tu Long" which can cut anything easily.

Now he put all pyramids on the ground (the usdersides close the ground)and cut a plane which is parallel with the water level by his sword ,call this plane cutting plane.

Our mission is to find a cutting plane that makes the sum of volume above the plane same as the below,and this plane is average cutting plane.Figure out the height of average cutting plane.

First line: $T$, the number of testcases.$( 1 \leq T \leq 100 )$

Then $T$ testcases follow.In each testcase print three lines :

The first line contains one integers $n(1 \leq n \leq 10000)$, the number of operations.

The second line contains $n$ integers $A_1, \ldots, A_n ( 1 \leq i \leq n, 1 \leq A_i \leq 1000)$ represent the height of the $ith$ pyramid.



The third line contains $n$ integers $B_1,\ldots, B_n ( 1 \leq i \leq n,1 \leq B_i \leq 100)$ represent the width of the $ith$ pyramid.

For each testcase print a integer - **the height of average cutting plane**.

(the results take the integer part,like 15.8 you should output 15)