Solution: Remove Invalid Parentheses
Explore how to apply backtracking to solve the problem of removing invalid parentheses from a string. Understand the recursive process of balancing parentheses, managing removals, and constructing all valid expressions. This lesson helps you develop a clear approach to tackling constraints and generating correct solutions in coding interviews.
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Statement
You are given a string, s, that contains:
Lowercase English letters
Opening
'('and closing')'parentheses
A string is considered valid if:
All opening parentheses
'('are closed properly by a matching')'.The parentheses are in the correct order and nesting.
Letters can appear anywhere and do not affect validity.
Return all possible valid strings that can be formed by removing the minimum number of invalid parentheses. The answer must be a list of unique strings, in any order.
Constraints:
s.lengthsconsists of lowercase English letters and parentheses'('and')'.There will be at most
20parentheses ins. ...