BacktrackingStringRecursion
Given n pairs of parentheses, print every well-formed combination of them, one per line, in lexicographic order (where ( comes before )).
Input
A single integer n.
Output
One valid string of length 2n per line, in lexicographic order.
Constraints
1 <= n <= 8
Example 1
Input
3
Output
((())) (()()) (())() ()(()) ()()()
Five valid strings, from ((())) to ()()().