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
Daniel Polaczanski:
20150107 22:47:34
Do I good understand that for 0101001 the answer is 4? 

Rishav Jain:
20141223 08:55:43
any1 can plz explain how the answer of 1 st case is 9,? 

Anuva Agarwal:
20141004 15:13:13
phew! :) 

AlcatraZ:
20141002 14:04:38
Nice one.. 

Aravindan Chandrasekaran:
20140917 14:13:40
Input string has more than 200 characters friends . 

selfcompiler:
20140811 20:59:27
simple Dp problem :) 

Bartosz Bednarczyk:
20140625 15:35:56
@RAM§DEN


nitesh kumar:
20140624 08:08:50
O(n^3) solution.. 

RAMSDEN:
20140619 10:09:45
Recursion gives tle


Harshit:
20140605 06:36:53
you need to lessen the time limit 
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 