ROCK  Sweet and Sour Rock
A manufacturer of sweets has started production of a new type of sweet called rock. Rock comes in sticks composed of onecentimetrelong segments, some of which are sweet, and the rest are sour. Before sale, the rock is broken up into smaller pieces by splitting it at the connections of some segments.
Today's children are very particular about what they eat, and they will only buy a piece of rock if it contains more sweet segments than sour ones. Try to determine the total length of rock which can be sold after breaking up the rock in the best possible way.
Input
The input begins with the integer t, the number of test cases. Then t test cases follow.
For each test case, the first line of input contains one integer N  the length of the stick in centimetres (1<=N<=200). The next line is a sequence of N characters '0' or '1', describing the segments of the stick from the left end to the right end ('0' denotes a sour segment, '1'  a sweet one).
Output
For each test case output a line with a single integer: the total length of rock that can be sold after breaking up the rock in the best possible way.
Example
Sample input: 2 15 100110001010001 16 0010111101100000 Sample output: 9 13
hide comments
arbit:
20140527 14:42:14
A test case I missed that can be helpful to you.


JordanBelfort:
20140207 16:06:04
Really nice one..:) 

Cloud Strife:
20140206 06:31:21
Nice question! 

harsh:
20131129 14:01:11
nyc problem.. 

Dragan MarkoviĆ¦:
20130721 18:59:28
I don't know if it's allowed but here's a little hint : When you have problem like this always think of regular expressions. 

Prajit Patil:
20130615 09:31:16
0000110100100


another_clone:
20130424 10:05:40
what should be the output for wrong cases ?


Prashant Mishra:
20120918 16:27:47
can someone tell some test cases... getting WA? 

KEVALSAHU:
20120826 01:10:50
simple problem guys :) Last edit: 20120826 01:15:23 

Caesum:
20110128 14:09:12
I think the pieces are 10011,101,1

Added by:  adrian 
Date:  20040803 
Time limit:  7s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All 
Resource:  based on a problem from the VII Polish Collegiate Team Programming Contest (AMPPZ), 2002 