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Problem: Minimum Remove to Make Valid Parentheses

Medium
30 min
Explore how to identify and remove unmatched parentheses to form a valid string expression. This lesson uses stacks to solve the problem of minimum removal needed, helping you understand string manipulation techniques for coding interviews.

Statement

Given a string, s, that may have matchedEach opening parenthesis, (, has a closing parenthesis, ), for it. and unmatchedThere is no corresponding closing parenthesis, ), for an opening parenthesis, (. parentheses, remove the minimum number of parentheses so that the resulting string represents a valid parenthesization. For example, the string “a(b)” represents a valid parenthesization while the string “a(b” doesn’t, since the opening parenthesis doesn’t have any corresponding closing parenthesis.

Constraints:

  • 11 \leq s.length 103\leq 10^3
  • s[i] is either an opening parenthesis (( , a closing parenthesiss )), or a lowercase English letter.
Problem
Ask
Submissions

Problem: Minimum Remove to Make Valid Parentheses

Medium
30 min
Explore how to identify and remove unmatched parentheses to form a valid string expression. This lesson uses stacks to solve the problem of minimum removal needed, helping you understand string manipulation techniques for coding interviews.

Statement

Given a string, s, that may have matchedEach opening parenthesis, (, has a closing parenthesis, ), for it. and unmatchedThere is no corresponding closing parenthesis, ), for an opening parenthesis, (. parentheses, remove the minimum number of parentheses so that the resulting string represents a valid parenthesization. For example, the string “a(b)” represents a valid parenthesization while the string “a(b” doesn’t, since the opening parenthesis doesn’t have any corresponding closing parenthesis.

Constraints:

  • 11 \leq s.length 103\leq 10^3
  • s[i] is either an opening parenthesis (( , a closing parenthesiss )), or a lowercase English letter.