FASHION  Fashion Shows
A fashion show rates participants according to their level of hotness. Two different fashion shows were organized, one for men and the other for women. A date for the third is yet to be decided ;) .
Now the results of both fashion shows are out. The participants of both the fashion shows have decided to date each other, but as usual they have difficuly in choosing their partners. The Maximum Match dating serive (MMDS) comes to their rescue and matches them in such a way that that maximizes the hotness bonds for all couples.
If a man has been rated at hotness level x and a women at hotness level y, the value of their hotness bond is x*y.
Both fashion shows contain N participants each. MMDS has done its job and your job is to find the sum of hotness bonds for all the couples that MMDS has proposed.
Input
The first line of the input contains an integer t, the number of test cases. t test cases follow.
Each test case consists of 3 lines:
 The first line contains a single integer N (1 <= N <= 1000).
 The second line contains N integers separated by single spaces denoting the hotness levels of the men.
 The third line contains N integers separated by single spaces denoting the hotness levels of the women.
All hotness ratings are on a scale of 0 to 10.
Output
For each test case output a single line containing a single integer denoting the sum of the hotness bonds for all pairs that MMDS has proposed.
Example
Input: 2 2 1 1 3 2 3 2 3 2 1 3 2 Output: 5 15
hide comments
phoemur:
20180904 19:16:46
In C++ just apply std::sort and std::inner_product 

anshuman1117:
20180815 09:10:08
Very easy problem. Just sort the two arrays, calculate hotness and then use an accumulator variable to calculate the sum. print it and get AC in 1 GO. lol 

sudhanshu_sing:
20180813 13:12:19
wrong explanation, u have to match the hotness of men and women first to maximize total hotness !! 

byte_b:
20180724 07:18:49
Use two stacks and store numbers in ascending order ( smaller first ). The. Just pop elements and multiply them. 

nishant1ranjan:
20180606 07:51:12
it is said that we have to maximise the hotness ,so we have to sort ,in order to multiply two no. to maximise the result 

janus_syrak:
20180523 21:30:58
The explanation is incorrect. You need to sort first, and then multiply. 

mahakaal2018:
20180503 10:30:09
AC in one go!!! 

ayush_1996:
20180328 14:11:05
AC in one go :D 

pshishod2645:
20180321 08:39:12
https://en.wikipedia.org/wiki/Rearrangement_inequality


zoyron:
20180227 23:37:13
wrong explanation of the question. 
Added by:  Matthew Reeder 
Date:  20061029 
Time limit:  0.970s 
Source limit:  30000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All except: ERL JSRHINO NODEJS PERL6 VB.NET 
Resource:  AlKhawarizm 2006 