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3

# Remove Invalid Parentheses

Difficulty: HARD
Contributed By
Avg. time to solve
50 min
Success Rate
50%

Problem Statement

#### Note:

``````1) A string is valid only if every left parenthesis has corresponding right parentheses in the same order.

For example Given ‘STR’ = (())()) is not a valid string, whereas ‘STR’ = (())() is a valid string.
``````

#### Input Format

``````The first line of input contains an integer 'T' representing the number of test cases.

The first and the only line of each test case contains a single string ‘STR’ representing the parenthesis.
``````

#### Output Format:

``````For each test case, return all possible unique, valid strings after removing the minimum number of parentheses.

The output of each test case will be printed in a separate line.
``````

#### Note:

``````You do not need to print anything, it has already been taken care of. Just implement the given function.
``````

#### Constraints:

``````1 <= T <= 5
1 <= |STR| <= 50

Time Limit: 1 second
``````

#### Sample Input 1:

``````2
(((a))()
)(()))
``````

#### Sample Output 1:

``````(((a))) ((a))()
(())
``````

#### Explanation of Sample Output 1:

``````Test Case 1 :
Given ‘STR’ = (((a))()
From this string, two valid strings can be generated after removing only one parenthesis, which is minimum.
One way is to remove the parenthesis at index 6 to generate (((a))).
Another way is to remove either the first, second, or third parenthesis, which will result in the same string, i.e., ((a))().

Test Case 2 :
Given ‘STR’ = )(()))
The minimum number of invalid parentheses required to be removed is 2. We have to remove the first and last parentheses to generate a valid string.
So the valid string is (()).
``````

#### Sample Input 2:

``````1
(()(()(())
``````

#### Sample Output 2:

``````()()(()) ()(()()) (())(()) (()()()) (()(()))
``````
Console