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JarviixAll problems

Valid Sudoku

Medium

Array · Hashing · Matrix~20m

Live AI Interview

00:00

Section 1Understand Problem

Section 01

Understand the problem

Restate the problem precisely. Interviewers reward candidates who pause, define the contract, and name the guarantees before coding.

Problem statement

Determine if a 9 x 9 Sudoku board is valid. Only the filled cells need to be validated according to the following rules: each row must contain the digits 1-9 without repetition; each column must contain the digits 1-9 without repetition; each of the nine 3 x 3 sub-boxes must contain the digits 1-9 without repetition. The Sudoku board could be partially filled, where empty cells are filled with the character `.`.

Example

board: standard valid example → true

Constraints

board.length == 9 · board[i].length == 9 · board[i][j] is a digit 1-9 or '.'

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WPM—Fillers0Pace—Thinking0%

Explain the problem in your own words

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AI Review

Write your thinking above first.

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The reviewer will check whether you stated inputs, output, guarantees, and any assumption you flagged.

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