import java.util.HashSet;
import java.util.Set;
// Sudoku solution must satisfy all of the following rules:
// Each of the digits 1-9 must occur once in each row.
// Each of the digits 1-9 must occur once in each column.
// Each of the digits 1-9 must occur once in each 3x3 grid.
public class SudokuValidator {
public static boolean isValidSudoku3x3Grid(int[][] grid) {
if (grid.length != 3 || grid[0].length != 3) {
return false; // Ensure it's a 3x3 grid
}
Set<Integer> seen = new HashSet<>();
for (int[] row : grid) {
for (int num : row) {
if (num < 1 || num > 9 || seen.contains(num)) {
return false; // Invalid if number is out of range or repeated
}
seen.add(num);
}
}
return true; // Valid if all numbers 1-9 appear exactly once
}
public static void main(String[] args) {
int[][] grid = {
{5, 3, 4},
{6, 7, 2},
{1, 9, 8}
};
if (isValidSudoku3x3Grid(grid)) {
System.out.println("The grid is a valid Sudoku grid!");
} else {
System.out.println("The grid is NOT a valid Sudoku grid!");
}
}
}
/*
run:
The grid is a valid Sudoku grid!
*/
