Question

I need help with the following and written in c++ thank you!:

1) replace the 2D arrays with vectors

2) add a constructor to the Sudoku class that reads the initial configuration from a file

3) adds a function to the Sudoku class that writes the final Sudoku grid to a file or to the standard output device, cout.

Sudoku.h

#pragma once
/* notes
sudoku()
default constructor
precondition : none
postcondition: grid is initialized to 0

sudoku(g[][9])
1-parameter constructor
precondition : g satisfies sudoku grid restrictions
postcondition: grid = g

void initialiizeSudokuGrid()
interactive function to prompt the user to specify the number of the partially filled grid
precondition : none
postcondition: grid is initialized to the number specified by the user

void initializeSudokuGrid(int g[][9])
function to initialize grid to g
precondition: g satisties sudoku grid restrictions
postcondition: grid = g

void printSudokuGrid()
function to print the sudoku

bool solveSudoku()
function to solve thesukoku problem
precondition : none
postcondition: if a solution exists, it returns true, otherwise it returns false

bool findEmptyGridSlot(int &row, int &col)
function to determine if the grid slot specified by row and col is empty
precondition : row and col refer to a grid slot
postcondition: returns true if grid[row][col] = 0, otherwise it returns false

bool canPlaceNum(int row, int col, int num)
function to determine if num can be placed in grid[row][col]
precondition : row and col refer to a grid slot
postcondition: returns true if num can be placed in grid[row][col], otherwise it returns false

bool numAlreadyInRow(int row, int num)
function to determine if num is in grid[row][]
precondition : row refers to a grid row and num is an integer inclusively between 1 and 9
postcondition: returns true if num is in grid[row][], otherwise it returns false

bool numAlreadyInCol(int col, int num)
function to determine if num is in grid[row][]
precondition : col refers to a grid column and num is an integer inclusively between 1 and 9
postcondition: returns true if num is in grid[][col], otherwise it returns false

bool numAlreadyInBox(int smallGridRow, int smallGridCol, int num)
function to determine if num is in the small grid that contains grid[smallGridRow][smallGridCol]
precondition : smallGridRow and smallGridCol refer to a grid slot, num is an integer inclusively between 1 and 9
postcondition: returns true if num is in small grid, otherwise it returns false
*/

class Sudoku
{
public:
   Sudoku();
   Sudoku(int g[][9]);
   void initializeSudokuGrid();
   void initializeSudokuGrid(int g[][9]);
   void printSudokuGrid();
   bool solveSudoku();
   bool findEmptyGridSlot(int &row, int &col);
   bool canPlaceNum(int row, int col, int num);
   bool numAlreadyInRow(int row, int num);
   bool numAlreadyInCol(int col, int num);
   bool numAlreadyInBox(int smallGridRow, int smallGridCol, int num);
private:
   int grid[9][9];
};

Sudoku.cpp

#include <iostream>
#include <string>
#include "sudoku.h"
using namespace std;

Sudoku::Sudoku(void)
{  
   initializeSudokuGrid();
}
Sudoku::Sudoku(int g[][9])
{
   initializeSudokuGrid(g);
}
void Sudoku::initializeSudokuGrid()
{
   for(int row = 0; row < 9; row++)
       for(int col = 0; col < 9; col++)
           grid[row][col] = 0;
}
void Sudoku::initializeSudokuGrid(int g[][9])
{
   for(int row = 0; row < 9; row++)
       for(int col = 0; col < 9; col++)
           grid[row][col] = g[row][col];
}
void Sudoku::printSudokuGrid()
{
   for(int row = 0; row < 9; row++)
   {
       for(int col = 0; col < 9; col++)
           cout << grid[row][col];
       cout << endl;
   }
}
bool Sudoku::solveSudoku()
{
   int row = 0, col = 0;
   if(findEmptyGridSlot(row, col))
   {
       for(int num = 1; num <= 9; num++)
       {
           if(canPlaceNum(row, col, num))
           {
               grid[row][col] = num;
               if(solveSudoku())
                   return true;
               grid[row][col] = 0;
           }
       }
return false;
   }
   else
       return true;
}
bool Sudoku::findEmptyGridSlot(int &row, int &col)
{
   for (row = 0; row < 9; row++)
       for (col = 0; col < 9; col++)
           if (grid[row][col] == 0)
               return true;
   row = -1;
   col = -1;
   return false;
}
bool Sudoku::canPlaceNum(int row, int col, int num)
{
   return !numAlreadyInRow(row, num) &&
       !numAlreadyInCol(col, num) &&
       !numAlreadyInBox(row, col, num);
}
bool Sudoku::numAlreadyInRow(int row, int num)
{
   for(int col = 0; col < 9; col++)
       if(grid[row][col] == num) return true;
   return false;
}
bool Sudoku::numAlreadyInCol(int col, int num)
{
   for (int row = 0; row < 9; row++)
       if (grid[row][col] == num) return true;
   return false;
}
bool Sudoku::numAlreadyInBox(int smallGridRow, int smallGridCol, int num)
{
   int beginSmallGridRow = smallGridRow - smallGridRow % 3;
   int endSmallGridRow = beginSmallGridRow + 3;
   int beginSmallGridCol = smallGridCol - smallGridCol % 3;
   int endSmallGridCol = beginSmallGridCol + 3;

   for (int row = beginSmallGridRow; row < endSmallGridRow; row++)
       for (int col = beginSmallGridCol; col < endSmallGridCol; col++)
           if (grid[row][col] == num)
               return true;
   return false;
}

Source.cpp

#include <iostream>
#include <string>
#include "Sudoku.h"
using namespace std;

int main()
{
   int g[][9] =
   {
       {6,0,3,0,2,0,0,9,0},
       {0,0,0,0,5,0,0,8,0},
       {0,2,0,4,0,7,0,0,1},
       {0,0,6,0,1,4,3,0,0},
       {0,0,0,0,8,0,0,5,6},
       {0,4,0,6,0,3,2,0,0},
       {8,0,0,2,0,0,0,0,7},
       {0,1,0,0,7,5,8,0,0},
       {0,3,0,0,0,6,1,0,5}
   };

   Sudoku sudoku1;
   sudoku1.printSudokuGrid();
   sudoku1.solveSudoku();
   cout << endl;
   sudoku1.printSudokuGrid();
   cout << endl;
   Sudoku sudoku2(g);
   sudoku2.solveSudoku();
   sudoku2.printSudokuGrid();
   cout << endl;
   sudoku2.solveSudoku();
   sudoku2.printSudokuGrid();
   cout << endl;
   system("pause");
   return 0;
}

Answer 1

1) To replace the 2D array with vectors just add  vector<vector <int> > grid in place of 2D array declaration.

2) Here is the comstrcutor that reads from the file

Sudoku::Sudoku(void)
{   
int value;
ifstream infile;
infile.open("File Name");
vector <int> tempVec;
   for (int s=0; s<=8; s++){
for (int i=0; i<=8; i++){
infile >> value;
tempVec.push_back(value);
}
grid.push_back(tempVec);
       tempVec.clear();  
   }
}

3) Here is the function the prints

void Sudoku::printSudokuGrid(){
for (int i=0;i<=8;i++) {
for (int j=0;j<=8;j++) {
if (grid[i][j]==0 || grid[i][j]=='0')
cout << " ";
else
cout << puzzle[i][j] << " ";
  
}
}
}

For any further doubts or clarification, comment down !