Leetcode 36. Valid Sudoku
Check a 9x9 Sudoku board is valid by verifying that no digit 1–9 (ignoring '.') appears more than once in any row, column, or 3x3 sub-box. Return true if all these constraints hold for the partially filled board.
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Mid May, 2026
Late April, 2026
Hackerrank codepair round, was asked Valid Sudoku,I couldn't code running solution, I was able to explain the approach and solution verbally, then proceeded to write code, I was not able to properly understand how to check for inner squares.
Early April, 2026
Determine if a 9x9 Sudoku board is valid. A valid Sudoku board will hold the following conditions: Each row must contain the digits 1-9 without repetition. Each column must contain the digits 1-9 without repetition. The 9 3x3 sub-boxes of the grid must also contain the digits 1-9 without repetition.
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