what i need to do in this question…i am not able to understand the concept of this question
Brackets all over
@dakshi Hi ,the problem says that you are given a string s, it’s length m and a number n. You have generate all possible pairs of a and b such that:
a + s + b is a valid sequence of brackets of length exactly n.
For example if you are given s = “))” and n = 6(m = 2 obviously) then you can generate following pairs of a and b to make a+s+b a valid sequence:
“()((” “))” “” // Remeber a and b can be blank also.
“((” “))” “()”
“(((” “))” “)”
“(()(” “))” “”
“((()” “))” “”
Hence, the ans for this testcase is 5. If there is no possible combination then print -1. Pls try the question now.
Hope this helps 
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