Sudoku Solution Validator

Sudoku Background

Sudoku is a game played on a 9×9 grid. The goal of the game is to fill all cells of the grid with digits from 1 to 9, so that each column, each row, and each of the nine 3×3 sub-grids (also known as blocks) contain all of the digits from 1 to 9.
(More info at: http://en.wikipedia.org/wiki/Sudoku)
Sudoku Solution Validator

Write a function validSolution/ValidateSolution/valid_solution() that accepts a 2D array representing a Sudoku board, and returns true if it is a valid solution, or false otherwise. The cells of the sudoku board may also contain 0’s, which will represent empty cells. Boards containing one or more zeroes are considered to be invalid solutions.

The board is always 9 cells by 9 cells, and every cell only contains integers from 0 to 9.
Examples

validSolution([
[5, 3, 4, 6, 7, 8, 9, 1, 2],
[6, 7, 2, 1, 9, 5, 3, 4, 8],
[1, 9, 8, 3, 4, 2, 5, 6, 7],
[8, 5, 9, 7, 6, 1, 4, 2, 3],
[4, 2, 6, 8, 5, 3, 7, 9, 1],
[7, 1, 3, 9, 2, 4, 8, 5, 6],
[9, 6, 1, 5, 3, 7, 2, 8, 4],
[2, 8, 7, 4, 1, 9, 6, 3, 5],
[3, 4, 5, 2, 8, 6, 1, 7, 9]
]); // => true

validSolution([
[5, 3, 4, 6, 7, 8, 9, 1, 2],
[6, 7, 2, 1, 9, 0, 3, 4, 8],
[1, 0, 0, 3, 4, 2, 5, 6, 0],
[8, 5, 9, 7, 6, 1, 0, 2, 0],
[4, 2, 6, 8, 5, 3, 7, 9, 1],
[7, 1, 3, 9, 2, 4, 8, 5, 6],
[9, 0, 1, 5, 3, 7, 2, 1, 4],
[2, 8, 7, 4, 1, 9, 6, 3, 5],
[3, 0, 0, 4, 8, 1, 1, 7, 9]
]); // => false

Solution below

import java.util.Arrays;

public class SudokuValidator {
    public static boolean check(int[][] sudoku) {
        return checkSudokuStatus(sudoku);
    }
  private static boolean checkSudokuStatus(int[][] grid) {
    for (int i = 0; i < 9; i++) {

        int[] row = new int[9];
        int[] square = new int[9];
        int[] column = grid[i].clone();

        for (int j = 0; j < 9; j ++) {
            row[j] = grid[j][i];
            square[j] = grid[(i / 3) * 3 + j / 3][i * 3 % 9 + j % 3];
        }
        if (!(validate(column) && validate(row) && validate(square)))
            return false;
    }
    return true;
}

private static boolean validate(int[] check) {
    int i = 0;
    Arrays.sort(check);
    for (int number : check) {
        if (number != ++i)
            return false;
    }
    return true;
}
}

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Reference:https://www.codewars.com/kata/529bf0e9bdf7657179000008/train/java

原文链接：Sudoku Solution Validator