Valid Parentheses
Understand how to check if a string contains valid parentheses with proper order and matching pairs using stack data structures. This lesson guides you through implementing an efficient O(n) time and space solution for parenthesis validation, an essential pattern in coding interviews for handling sequential data.
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Statement
Given a string that may consist of opening and closing parentheses, your task is to check whether or not the string contains valid parenthesization.
The conditions to validate are as follows:
-
Every opening parenthesis should be closed by the same kind of parenthesis. Therefore,
{)and[(])strings are invalid. -
Every opening parenthesis must be closed in the correct order. Therefore,
)(and()(()are invalid.
Constraints:
-
s.length - The string will only contain the following characters:
(,),[,],{and}.
Examples
Understand the problem
Let’s take a moment to make sure you’ve correctly understood the problem. The quiz below helps you check if you’re solving the correct problem:
Valid Parentheses
Are the parentheses in the following string valid or not?
“(){}[]”
Not valid
Valid
Figure it out!
We have a game for you to play. Rearrange the logical building blocks to develop a clearer understanding of how to solve this problem.
Note: As an additional challenge, we have intentionally hidden the solution to this puzzle.
Try it yourself
Implement your solution in main.go in the following coding playground.
We have left the solution to this challenge as an exercise for you. The optimal solution to this problem runs in O(n) time and takes O(n) space. You may try to translate the logic of the solved puzzle into a coded solution.
package mainfunc isValid(s string) bool {// Replace this placeholder return statement with your codereturn true}