using System;

public class Program

{

    public static void Main()

    {

        int[][] letstestit =

        {

                new int[] { 1,3,2,5,4,6,9,8,7 }, 

                new int[] { 4,6,5,8,7,9,3,2,1 }, 

                new int[] { 7,9,8,2,1,3,6,5,4 }, 

                new int[] { 9,2,1,4,3,5,8,7,6 }, 

                new int[] { 3,5,4,7,6,8,2,1,9 }, 

                new int[] { 6,8,7,1,9,2,5,4,3 }, 

                new int[] { 5,7,6,9,8,1,4,3,2 }, 

                new int[] { 2,4,3,6,5,7,1,9,8 }, 

                new int[] { 8,1,9,3,2,4,7,6,5 } 

        };

        Console.WriteLine(sudoku(letstestit));

    }

    /**     [0][0]-[0][2] || [0][3]-[0][5] || [0][6]-[0][8]

            [2][0]-[2][2] || [2][3]-[2][5] || [2][6]-[2][8]

            --------------||---------------||--------------

            [3][0]-[3][2] || [3][3]-[3][5] || [3][6]-[3][8] 

            [5][0]-[5][2] || [5][3]-[5][5] || [5][6]-[5][8]

            --------------||---------------||--------------

            [6][0]-[6][2] || [6][3]-[6][5] || [6][6]-[6][8]

            [8][0]-[8][2] || [8][3]-[8][5] || [8][6]-[8][8]

    **/

    public static bool sudoku(int[][] gridIn) {

        bool row = true;

        bool column = true;

        bool grid = true;

        int check5s = 0;

        int testint = 45;

        for(int i = 0; i < gridIn.Length; i++)

        {

            int sums = 0;

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

            { sums += gridIn[i][j]; if(gridIn[i][j] == 5) {check5s++;}}

            if(sums != testint || check5s > 1)

                row = false;

            sums = 0;

            check5s = 0;

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

            { sums += gridIn[j][i];  if(gridIn[j][i] == 5) {check5s++;}}

            if(sums != testint)

                column = false;

            check5s = 0;

        }

        int sumsgrid1 = 0;

        int sumsgrid2 = 0;

        int sumsgrid3 = 0;

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

        {

            //Check top grids

            if(i < 3)

            {

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

                {

                    if(j < 3)

                        sumsgrid1 += gridIn[i][j];

                    if(j > 2 && j < 6)

                        sumsgrid2 += gridIn[i][j];

                    if(j > 5)

                        sumsgrid3 += gridIn[i][j];

                }

            }

            //reset

            if(i == 3)

            {

                if(sumsgrid1 != testint || sumsgrid2 != testint || sumsgrid3 != testint)

                    grid = false;

                sumsgrid1 = 0; sumsgrid2 = 0; sumsgrid3 = 0;

            }

            //Check middle grids

            if( i > 2 && i < 6)

            {

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

                {

                    if(j < 3)

                        sumsgrid1 += gridIn[i][j];

                    if(j > 2 && j < 6)

                        sumsgrid2 += gridIn[i][j];

                    if(j > 5)

                        sumsgrid3 += gridIn[i][j];

                }

            }

            //reset

            if(i == 5)

            {

                if(sumsgrid1 != testint || sumsgrid2 != testint || sumsgrid3 != testint)

                    grid = false;

                sumsgrid1 = 0; sumsgrid2 = 0; sumsgrid3 = 0;

            }

            //Check bottom grids

            if( i > 5)

            {

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

                {

                    if(j < 3)

                        sumsgrid1 += gridIn[i][j];

                    if(j > 2 && j < 6)

                        sumsgrid2 += gridIn[i][j];

                    if(j > 5)

                        sumsgrid3 += gridIn[i][j];

                }

            }

            //reset

            if(i == 8)

            {

                if(sumsgrid1 != testint || sumsgrid2 != testint || sumsgrid3 != testint)

                    grid = false;

                sumsgrid1 = 0; sumsgrid2 = 0; sumsgrid3 = 0;

            }

        }

        return (row && column && grid);

    }

}

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