Jumping into c++ chapter 14 problem 5 (Collect 4)

Hi guys I m trying to do a couple of functions which enable to get a board of a certain width and length. Once the user choose how much broad the board will be, I want to make appear on each empty slot this "-", by using system ("cls") (because is the only way I ve learnt so far).
This is the code I ve written:

Code:

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#include <iostream>
#include <cstdlib>

using namespace std;

void DisplayBoard (char **p_p_board, int length, int width);

void Board (char **p_p_board, int length, int width)
{
  p_p_board = new char* [length];
  for (int i=0; i<length; i++)
  {
    p_p_board [i] = new char [width];
  }
  DisplayBoard (p_p_board,  length,  width);
}

void DisplayBoard (char **p_p_board, int length, int width)
{
    cout<<"COLLECT FOUR"<<endl;
    system("cls");
    for (int x=1; x<length+1; x++)
    {
        cout<<x<<" ";
    }
    cout<<endl;
    for (int i =0; i<length; i++)
    {
        cout<<endl;
        for(int j=0; j<width; j++)
        {
          cout<< p_p_board [i][j] = "-"<< " "; // error
        }
    }
}

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I know it doesn't give anything yet, cause I haven t put main, but when I try to build it it tells me:
"|30|error: invalid operands of types 'const char [2]' and 'const char [2]' to binary 'operator<<'"
This is referred to the line of code where I added the comment "//error"
Could anyone tell me what to change?
(P.S. this chapter is supposed to treat multidimentional arrays and pointers to pointers)

Perhaps start with.
cout<< p_p_board [i][j];
Then add to it.

It's called "connect 4" (not "collect").

The assignment:

Quote:

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Write a two-player game of "connect 4" where the user can set the width and height of the board and each player gets a turn to drop a token into the slot. Display the board using + for one side, x for the other, and _ to indicate blank spaces.

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Code:

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#include <iostream>
#include <iomanip>
#include <cstdlib>
using namespace std;
 
void DisplayBoard(char **p_p_board, int length, int width);
 
char **Board(int length, int width) {
    char **p_p_board = new char*[length];
    for (int i = 0; i < length; i++) {
        p_p_board[i] = new char[width];
        for (int j = 0; j < width; j++)
            p_p_board[i][j] = '_';
    }
    return p_p_board;
}

void DisplayBoard(char **p_p_board, int length, int width) {
    //system("cls");
    cout << setw(3*width/2+7) << "CONNECT FOUR\n";
    for (int x = 1; x <= width; x++)
        cout << setw(2) << x << ' ';
    for (int i = 0; i < length; i++) {
        cout << "\n ";
        for (int j = 0; j < width; j++)
          cout << p_p_board[i][j] << "  ";
    }
    cout << '\n';
}

int main() {
    int length = 0, width = 0;
    cout << "Length: ";
    cin >> length;
    cout << "Width: ";
    cin >> width;

    char **p_p_board = Board(length, width);

    DisplayBoard(p_p_board, length, width);

    for (int i = 0; i < length; i++)
        delete [] p_p_board[i];
    delete [] p_p_board;
}

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Thanks a lot, i just didnt get wht setw(2) mean (you ve written it at the 20th and 22nd line)… I ve probably not arrived so far in my book yet. could you explain me what it is please? :)

setw(n) sets the "width" of the next field to n.
So

Code:

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cout << setw(3*width/2+7) << "CONNECT FOUR\n";

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sets the field width to what is required to center the title.

And

Code:

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cout << setw(2) << x << ' ';

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sets the field width to 2 so that single digit numbers will be printed with a space in front of them.