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How to Solve Valid Tic-Tac-Toe State Problem
Master the Valid Tic-Tac-Toe State LeetCode problem with undetectable real-time assistance. Get instant solutions and explanations during your coding interviews.
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Medium#794
LeetCode ProblemValid Tic-Tac-Toe State
Given a Tic-Tac-Toe board as a string array board, return true if and only if it is possible to reach this board position during the course of a valid tic-tac-toe game. The board is a 3 x 3 array that consists of characters ' ', 'X', and 'O'. The ' ' character represents an empty square. Here are the rules of Tic-Tac-Toe:
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Problem Breakdown
Understanding the Valid Tic-Tac-Toe State Problem
Let's break down this LeetCode problem and understand what makes it challenging in interview settings.
Problem Statement
Given a Tic-Tac-Toe board as a string array board, return true if and only if it is possible to reach this board position during the course of a valid tic-tac-toe game. The board is a 3 x 3 array that consists of characters ' ', 'X', and 'O'. The ' ' character represents an empty square. Here are the rules of Tic-Tac-Toe:
Examples
# Example 1
Input
board = ["O "," "," "]
Output
false
# Example 2
Input
board = ["XOX"," X "," "]
Output
false
# Example 3
Input
board = ["XOX","O O","XOX"]
Output
true
Constraints
board.length == 3
board[i].length == 3
board[i][j] is either 'X', 'O', or ' '.
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Solve Valid Tic-Tac-Toe State — Given a Tic-Tac-Toe board as a string array board, return true if and only if it...
Here's the optimal approach using Array:
def solve(input):
# Optimal O(n) solution
return result
Time: O(n) | Space: O(n)
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Frequently Asked Questions
Common questions about solving Valid Tic-Tac-Toe State and using PhantomCodeAI during coding interviews.
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PhantomCodeAI reads the problem from a screenshot or listens to it via audio, then generates a complete solution with a step-by-step approach and time/space complexity, so you can focus on explaining your reasoning rather than getting stuck on implementation.
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Should I still practice these problems on my own first?
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