ANARC09A  Seinfeld
I’m out of stories. For years I’ve been writing stories, some rather silly, just to make simple problems look difficult and complex problems look easy. But, alas, not for this one.
You’re given a non empty string made in its entirety from opening and closing braces. Your task is to find the minimum number of “operations” needed to make the string stable. The definition for being stable is as follows:
 An empty string is stable.
 If S is stable, then {S} is also stable.
 If S and T are both stable, then ST (the concatenation of the two) is also stable.
All of these strings are stable: {}, {}{}, and {{}{}}; But none of these: }{, {{}{, nor {}{.
The only operation allowed on the string is to replace an opening brace with a closing brace, or visaversa.
Input
Your program will be tested on one or more data sets. Each data set is described on a single line. The line is a nonempty string of opening and closing braces and nothing else. No string has more than 2000 braces. All sequences are of even length.
The last line of the input is made of one or more ’’ (minus signs.)
Output
For each test case, print the following line:
k. N
Where k is the test case number (starting at one,) and N is the minimum number of operations needed to convert the given string into a balanced one.
Example
Input: }{
{}{}{}
{{{}

Output: 1. 2
2. 0
3. 1
hide comments
ramini1996:
20190410 19:25:18
No need of DP at all...!!! 

gaurav__404:
20190323 16:54:51
Again ... why is it tagged DP ( might be due to ............ ) 

tarungupta:
20190311 17:36:58
AC in 1 go. Stack implementation. 

sabbirh654:
20190120 11:56:57
it's not a contest platform.if you can solve without stack,try it with satck.it will boost up your skills and ideas.


sabbirh654:
20190120 11:15:37


shubham:
20190115 16:19:19
It did require some analysis to solve using stack. Observing the final unbalanced string must be of the form }}}... {{{.. which is closed followed by opens.


vcode11:
20190105 07:51:35
I got a score for this problem what does iit mean?


ducluong:
20181027 15:21:02
obviously stack is enough to solve this problem, but can you give me some advise to solve this in dp 

amitnsky:
20180906 18:21:21
using stack will also give you correct ans becoz


logic_bomb:
20180729 07:50:10
Last edit: 20180729 07:56:32 
Added by:  Mohammad Kotb 
Date:  20091128 
Time limit:  3.236s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All except: ASM64 BASH JSRHINO 
Resource:  http://www.icpcanarc.org 