Brackets All Over

#1

please explain the question and help me in approaching this question

#2

Hey!
Let me explain the sample input step by step
input:
4 2
((
here n=4, m=2 and s=((

Now here s is the given string that we are talking about, m is the size of s (which is 2 in this case), we have to form a new string whose size is given to us- n(4 in this case)

Now, talking about the new string, we have to form it by appending a string a before it and by appending a string b after string s (This is what a+s+b means).
Now in our sample test case we are given n=4, m=2, s=((
we have to form a string of length 4, now that can only be (()), because we have to balance the brackets, we can NOT form a string like: ((() or ())(
therefore to form (()) we have one option a=""{i.e. a blank string} and b="))" {string with 2 closing brackets}.
Try solving this question using DP