Having trouble with implentation file

I'm having trouble getting the implementation file to work correctly.

interface file

Code:

---

#ifndef GAMEBOARD_H
#define GAMEBOARD_H

#include <vector>
#include <iostream>

/*
A class that encapsulates a game board. Each position
on the game board can hold a single character,
by default space. Initially, the gameboard is empty
and the size is 0x0. If the user attempts to set
a character to a position outside of the current
coordiates, the size of the board will automatically
expand. If the user attempts to get a character
outside of the current size, it will return a space.
*/
class GameBoard
{
public:
        //construct an initially empty board
        GameBoard();

        //do-nothing destructor
        ~GameBoard();

        //set the character at position x,y,
        //expanding if necessary
        void set(int x, int y, char val);

        //get the character at position x,y
        char get(int x, int y);

        //set reference parameters x and y
        //to the current maximum extents
        //of the board
        void getSize(int &x, int &y);

        //write the board to the given
        //output stream
        void print(std::ostream &out);
private:
        //stores the data as a vector of vectors
        std::vector<std::vector<char> > data;
};

#endif

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implementation file

Code:

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//g++ -o gameboard.out gameboard.cpp mygame.cpp

#include "gameboard.h"
#include <iostream>

using namespace std;
////////////////////////////////////////////////////////////
GameBoard::~GameBoard()
{
 // Just leave it blank
}
////////////////////////////////////////////////////////////
GameBoard::GameBoard()
{
    int x = 0;
    int y = 0;
 
 
}
////////////////////////////////////////////////////////////
void GameBoard::set(int x, int y, char val)
{
    while (x<0||y<0);
    {
        if (data.size()<=x)
        data.resize(x+1);
        if (data[x].size()<=y)
        data[x].resize(y+1,' ');
        data[x][y]= val;
         
         
    }
 
}

////////////////////////////////////////////////////////////
char GameBoard::get(int x, int y)
{ 
    char value;
    if(x<data[x].size() && y <data[x-1].size()) // use same as the get size
    {
        return data[x][y];
    }
        else
        {
            return ' ';
        }
}

////////////////////////////////////////////////////////////
void GameBoard::getSize(int &x, int &y)
{
 
// get vecotr of vectors largest hgeight for the y=value
// the x-value is the vector of vectors
    x = data.size();
    y = data[x-1].size(); // minus 1
    //cout<<"4"<<endl;

}

////////////////////////////////////////////////////////////
void GameBoard::print(std::ostream &out)
{
 
        for (int i=0; i<data.size(); i++)
        {
            for (int j=0; j<data[i].size();j++)
            {
            char theChar = data[i][j];
            out<<theChar;
            }
        out<<endl;
        } 
 
    //cout<<"5"<<endl;

}
////////////////////////////////////////////////////////////

---

cpp source file

Code:

---

#include "gameboard.h"
#include <iostream>

using namespace std;

void setup(GameBoard &a)
{
        for (int i = 0; i < 30; i++)
        {
                a.set(i,0,'!');
                a.set(i,10,'!');
        }
        for (int i = 1; i < 10; i++)
        {
                a.set(0,i,'#');
                a.set(29,i,'#');
        }
}

int main()
{
        GameBoard game;
        setup(game);
        game.set(3,8,'?');
        cout << "Position at 56,70 is " << game.get(56,70) << endl;
        cout << "Position at 0,0 is " << game.get(0,0) << endl;
        game.print(cout);
        return 0;
}

---

Quote:

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Originally Posted by aurorablaze07

I'm having trouble getting the implementation file to work correctly.

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Maybe you want to tell us about your trouble? Few people here are mind readers....

what is the error?

The two lines in the constructor serve no purpose at all. -commented from my teacher so i need to fix


The loop you've defined in the set() is infinite, so call to set with invalid parameters will hang. Furthermore, if the parameters are valid, then the function does nothing.



getSize will return the wrong information.

Quote:

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Originally Posted by aurorablaze07

The two lines in the constructor serve no purpose at all. -commented from my teacher so i need to fix

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You are declaring local variables x and y and setting them instead of the object variables. Don't declare variables in the constructor, just set them.

Quote:

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Originally Posted by aurorablaze07

The loop you've defined in the set() is infinite, so call to set with invalid parameters will hang. Furthermore, if the parameters are valid, then the function does nothing.

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I don't understand as it's not clear to me what are valid and invalid parameters. If only positive values are allowed, then the parameters should be declared as unsigned int.

Quote:

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Originally Posted by aurorablaze07

getSize will return the wrong information.

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Test with coordinates (0,5) and (3,0). What's the real size, what will your function return?

Quote:

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Originally Posted by aurorablaze07

The loop you've defined in the set() is infinite, so call to set with invalid parameters will hang. Furthermore, if the parameters are valid, then the function does nothing.

Code:

---

void GameBoard::set(int x, int y, char val)
{
    while (x<0||y<0);
    {
        if (data.size()<=x)
        data.resize(x+1);
        if (data[x].size()<=y)
        data[x].resize(y+1,' ');
        data[x][y]= val;
         
         
    }

---

---

Your while statement is terminated by the semi-colon you've included.

Even without the semicolon, the statement runs only if x is negative or y is negative. Since size can never be negative data.size() can never be less than x when x is negative and it can never be less than y when y is negative. So it x and y are both less than 0, the loop runs indefinitely.

Rather than just looping and resizing by 1 every time, why not just figure out how much you need to resize by and do it in one statement.