8 queens c++ Print by 8 by 8 array all 0

Question

#include <iostream>

using namespace std;

#define N 8

class queen_solver
{
private:

    bool board[N][N] = {{false}};

public:

    queen_solver() = default;
    bool place_queens();
    bool place_queen_in_row(int);
    bool is_safe(int, int) const;
    void print_solution() const;
};


int main()
{
    queen_solver q;

     if(q.place_queens())
        q.print_solution();

    else
        cout << "Error - no solution found\n";

    return 0;
}

 bool queen_solver::place_queens()
{
  return  place_queen_in_row(0);
}

 bool queen_solver::place_queen_in_row(int row)
{
    // All queens have been placed successfully.
    if (row >= N)
        return true;

    for (int col = 0; col < N; col++)
    {
        if (is_safe(row, col))
        {
            // queen at board[row][col]
 if (place_queen_in_row(row + 1))
             {
                // All queens in rows below this one
                // have been successfully placed.
                return true;
            }


        }
    }

    // we were not able to place a queen anywhere in
    // this row.
    return false;
}


 bool queen_solver::is_safe(int row, int col) const
{

    int r;
    int c;

    for (r = 0; r < row; r++)
    {
        if (board[r][col])
        {
           return false;
        }
    }

    for (r = row, c = col; r >= 0 && c >= 0; r--, c--)
    {
        if (board[r][c])
        {

           return false;
        }
    }

    for (r = row, c = col; r >= 0 && c < N; c++, r--)
    {
        if (board[r][c])
        {
           return false;
        }

    }
    return true;
}

 void queen_solver::print_solution() const
 
{

  int r;
  int c;

   for (r = 0; r < N; r++)
   {
      for (c = 0; c < N; c++)
      {
            cout <<board[r][c] << " ";


      }
   cout << endl;

   }

}

Just wondering what I'm doing wrong here and why I'm only getting an 8 by 8 array with all 0s and no 1s to represent the queens. I have been trying to fix it for hours and I feel like it is just a dumb little mistake. If you could let me know what I did wrong that would be really appreciated Thank you! OutPut