#include <stdio.h>
//Puzzle: http://www.puzzles.ca/sudoku_puzzles/sudoku_easy_183.html Solution: http://www.puzzles.ca/sudoku_puzzles/sudoku_easy_183_solution.html
int main(){
    int boxStart;
    int horLineStart;
    int vertLineStart;
    int x[82];
    int numbersAvailable[10];
    int numberOfZero;
    for (int i = 1; i < 82; i++){x[i] = 0;}
    x[1] = 8;//Rad1
    x[2] = 3;
    x[7] = 9;
    x[8] = 1;

    x[10] = 5;//Rad2
    x[17] = 2;

    x[19] = 6;//Rad3
    x[20] = 2;
    x[21] = 4;
    x[22] = 3;
    x[27] = 8;

    x[28] = 9;//rad4
    x[34] = 3;
    x[35] = 5;
    x[36] = 7;

    x[39] = 1;//rad5
    x[40] = 7;
    x[42] = 5;
    x[45] = 9;

    x[53] = 8;//rad6

    x[62] = 9;//rad7

    x[64] = 2;//rad8
    x[65] = 6;
    x[68] = 3;

    x[76] = 2;//rad9
    x[77] = 5;
    x[81] = 6;

    for (int i = 1; i <= 3; i++){
        boxStart =
        numberOfZero = 0;
        for (int a = 1; a <= 9; a++){
            numbersAvailable[a] = a;
        }
        //Remove numbers in the box(3x3) from numbersAvailable
        for (int c = 0; c < 3; c++){
            for (int b = 0; b < 3; b++){
                for (int a = 1; a <= 9; a++){
                    if (x[i + b + (c*9)] == a){
                        numbersAvailable[a] = 0;
                    }
                }
            }
        }
        //Remove numbers from horizontal line
        for (int b = 0; b < 9; b++){
            for (int a = 1; a <= 9; a++){
                if (x[i+b] == a){
                    numbersAvailable[a] = 0;
                }
            }
        }
        //Remove numbers from Vertical line
        for (int b = 0; b < 9; b++){
            for (int a = 1; a <= 9; a++){
                if (x[i + (b*9)] == a){
                    numbersAvailable[a] = 0;
                }
            }
        }
        /*Reads number of zeroes in numbersAvailable
        for (int a = 1; a <= 9; a++){
            if (numbersAvailable[a] = 0)
                numberOfZero++;
        }
        */
        //Puts a new number in the box.
        if (x[i] != 0 && numberOfZero == 8){
            for (int a = 1; a < 9; a++){
                if (numbersAvailable[a] != 0){
                    x[i] = numbersAvailable[a];
                }
            }
        }
        if ((i-1) % 9 == 0){
            printf("\n");
        }
        //printf("%d ",x[i]);
        //Print numbersAvailable
        for (int a = 1; a <= 9; a++){
            printf("%d ", numbersAvailable[a]);
        }
        printf("\n");
    }
    getchar();
    return 0;
}