// Write a program to solve a Sudoku puzzle by filling the empty cells.

// Empty cells are indicated by 0.

// You may assume that there will be only one unique solution.

// Input: https://www.screencast.com/t/WfKc0wUWHi

​

// Output: https://www.screencast.com/t/qNLm0Kh59cz

​

​

using System;

using System.Text;

public class Program

{

    public static void Main()

    {

        var board = new int[9, 9]

        {

            {5,3,0,0,7,0,0,0,0},

            {6,0,0,1,9,5,0,0,0},

            {0,9,8,0,0,0,0,6,0},

            {8,0,0,0,6,0,0,0,3},

            {4,0,0,8,0,3,0,0,1},

            {7,0,0,0,2,0,0,0,6},

            {0,6,0,0,0,0,2,8,0},

            {0,0,0,4,1,9,0,0,5},

            {0,0,0,0,8,0,0,7,9}

        };

        SolveSudoku(board);

    }

​

    public  static void SolveSudoku(int[,] board) 

    {

        Console.WriteLine("Input");

        WriteBoard(board);

        //Solve here

        //...

        Console.WriteLine("Output");

        WriteBoard(board);

        //Test here

        //Write a test to make sure output has correct data

    }

    public static void WriteBoard(int[,] board)

    {

        StringBuilder sb = new StringBuilder();

        sb.AppendLine("-------------------------------------");

        for (int i=0; i < 9; i++)

        {

            sb.Append("| ");

            for (int j=0; j < 9; j++)

            {

                sb.Append(board[i, j] + " | ");

            }

            sb.AppendLine();

            sb.AppendLine("-------------------------------------");

        }

        Console.WriteLine(sb.ToString());

    }

}