int numberIn3x3(int array[9][9], int a, int b, int val)
        {
        int i, j, logvar = 0;
        for (i = (a/3)*3; i<= (a/3)*3+2; i++) {
                for (j = (b/3)*3; j <= (b/3)*3+2; j++)
                        if (array[i][j] == val) logvar = 1;};

        return logvar;}

        int numberInRow(int array[9][9], int a, int val)
        {
        int b, logrow = 0;
        for (b = 0; b < 9; b++) {
                if (array[a][b] == val) logrow = 1;}
        return logrow;
        }

        int numberInCol(int array[9][9], int a, int val)
        {
        int b, logcol = 0;
   for (b = 0; b < 9; b++) {
                if (array[b][a] == val) logcol = 1;}
        return logcol;
        }

        int validnumber(int a)
        {
        if (a<1 || a>9) return 0 ; return 1;
        }

        int emptyCell(int array[9][9], int a, int b)
        {
        if ( array[a][b] == 0 ) return 0 ; return 1;
        }