PRATA  Roti Prata
IEEE is having its AGM next week and the president wants to serve cheese prata after the meeting. The subcommittee members are asked to go to food connection and get P(P<=1000) pratas packed for the function. The stall has L cooks(L<=50) and each cook has a rank R(1<=R<=8). A cook with a rank R can cook 1 prata in the first R minutes 1 more prata in the next 2R minutes, 1 more prata in 3R minutes and so on(he can only cook a complete prata) ( For example if a cook is ranked 2.. he will cook one prata in 2 minutes one more prata in the next 4 mins an one more in the next 6 minutes hence in total 12 minutes he cooks 3 pratas in 13 minutes also he can cook only 3 pratas as he does not have enough time for the 4th prata). The webmaster wants to know the minimum time to get the order done. Please write a program to help him out.
Input
The first line tells the number of test cases. Each test case consist of 2 lines. In the first line of the test case we have P the number of prata ordered. In the next line the first integer denotes the number of cooks L and L integers follow in the same line each denoting the rank of a cook.
Output
Print an integer which tells the number of minutes needed to get the order done.
Example
Input:
3
10
4 1 2 3 4
8
1 1
8
8 1 1 1 1 1 1 1 1
Output:
12
36
1
hide comments
ayush_130:
20200529 20:40:54
First time in a while in one go 

bhati_r45:
20200515 17:14:22
binary search jinda baad


az_09_18je0028:
20200418 20:16:02
brilliant one,mind blowing...the use of quadratic equation is awesome::)today i ate parathas because of this ::)lol..


smso:
20200415 08:40:51
quadratic sequence 

deepu2345:
20200414 19:38:34
accepted :) 

arsundram:
20200404 23:04:54
AC in one Go!! ;) 

dkkv0000:
20200127 12:34:13
binary search + quadratic equation rocks 

aj54:
20191224 15:41:37
Binary Search and AC in one go! 

scorpy1:
20190913 18:09:59
AC with Binary Search 

aayush_b1999:
20190803 22:56:35
let max_rank=(the max rank in the given array)

Added by:  Saransh Bansal 
Date:  20110514 
Time limit:  1s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All except: ASM64 
Resource:  Own problem NTU IEEE codejam 2011 