Chapter 1, Problem 1CRP

Critical Thinking Sudoku is a puzzle consisting of squares arranged in 9 rows and 9 columns. The 81 squares are further divided into nine 3 × 3 square boxes. The object is to fill in the squares with numerals 1 through 9 so that each column, row, and box contains all nine numbers. However, there is a requirement that each number appear only once in any row, column, or box. Each puzzle already has numbers in some of the squares. Would it be appropriate to use a random-number table to select a digit for each blank square? Explain.

To determine

Explain whether it would be appropriate to use a random-number table for selecting a digit for each blank square in Sudoku.

Answer to Problem 1CRP

No, it would not be appropriate to use a random-number table for selecting a digit for each blank square in Sudoku.

Explanation of Solution

In Sudoku each of the number must appear only once in row, column or box. A random number table cannot be used for selecting number because the numbers in Sudoku are not filled randomly. It would be better to fill the boxes by looking at the existing numbers in the puzzle based on the requirement that number must appear only once in row, column or box.