Solution: Remove Invalid Parentheses
Explore how to solve the problem of removing invalid parentheses from a string using a backtracking algorithm. This lesson shows you how to identify and remove the minimum number of invalid parentheses while generating all unique, valid expressions. Understand recursive decision-making, balancing parentheses, and handling string constraints to implement an optimal backtracking solution.
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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:
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