Sudoku - 2/12/19

//sudoku.h
#include <iostream>
#include <fstream>
#include <stdlib.h>
#include <time.h>
using namespace std;
#define SIZE 9

class Sudoku {
private:
    int **grid;
public:
    Sudoku();
    ~Sudoku();
    void genPuzzleFromFile(char *fname);
    void printPuzzle();
    bool const isValidRow(int x, int y, int value);
    bool const isValidCol(int x, int y, int value);
    bool const isValidBox(int x, int y, int value);
    bool const isValid(int x, int y, int value);
    bool const solve();
};




//main.cpp
int main(int argc, char *argv[])
{
    Sudoku puzzle;
    /*
    if (argc == 1)
        puzzle.genPuzzle(1);
    else*/

    puzzle.genPuzzleFromFile(argv[1]);

    puzzle.printPuzzle();
    puzzle.solve();
    puzzle.printPuzzle();
    cin.get(), cin.get();
}




//sudoku.cpp
Sudoku::Sudoku() {
    grid = new int*[SIZE];
    for (int i = 0; i < SIZE; i++) grid[i] = new int[SIZE];
    for (int x = 0; x < SIZE; x++)
        for (int y = 0; y < SIZE; y++)
            grid[x][y] = 0;
}

Sudoku::~Sudoku() {
    for (int i = 0; i < SIZE; i++) delete[] grid[i];
    delete[] grid;
}

void Sudoku::genPuzzleFromFile(char *fname) {
    ifstream inputFile;
    inputFile.open(fname);
    for (int i = 0; i < SIZE; i++)
        for (int j = 0; j < SIZE; j++)
            inputFile >> grid[i][j];
    inputFile.close();
}
//void Sudoku::genPuzzle(int level) {}
void Sudoku::printPuzzle() {
    cout << "------------------\n";
    for (int i = 0; i < SIZE; i++) {
        for (int j = 0; j < SIZE; j++) {
            cout << "|" << grid[i][j];
        }
        cout << "|" << endl;
    }
    cout << "------------------\n";
}
bool const Sudoku::isValidRow(int x, int y, int value) {
    for (int i = 0; i < SIZE; i++) {
        if (y != i && grid[x][i] == value)
            return false;
    }
    return true;
}
bool const Sudoku::isValidCol(int x, int y, int value) {
    for (int i = 0; i < SIZE; i++) {
        if (x != i && grid[i][y] == value)
            return false;
    }
    return true;
}

bool const Sudoku::isValidBox(int x, int y, int value) {
    int box, row, col;

    row = (x / 3) * 3;
    col = (y / 3) * 3;
    for (int i = row; i < row + 3; i++) {
        for (int j = col; j < col + 3; j++) {
            if (i != x && j != y)
                if (grid[i][j] == value)
                    return false;
        }
    }
    return true;
}
bool const Sudoku::isValid(int x, int y, int value) {
    if (isValidRow(x, y, value) &&
        isValidCol(x, y, value) &&
        isValidBox(x, y, value))
        return true;
    return false;
}
bool const Sudoku::solve() {
    for (int i = 0; i < SIZE; i++) {
        for (int j = 0; j < SIZE; j++) {
            if (grid[i][j] == 0) {
                for (int k = 1; k <= SIZE; k++) {
                    if (isValid(i, j, k)) {
                        grid[i][j] = k;
                        if (solve()) return true;
                        else grid[i][j] = 0;
                    }
                }
                return false;
            }
        }
    }
    return true;
}

/* Puzzle.txt
0 0 3 0 2 0 6 0 0
9 0 0 3 0 5 0 0 1
0 0 1 8 0 6 4 0 0
0 0 8 1 0 2 9 0 0
7 0 0 0 0 0 0 0 8
0 0 6 7 0 8 2 0 0
0 0 2 6 0 9 5 0 0
8 0 0 2 0 3 0 0 9
0 0 5 0 1 0 3 0 0
*/