怎样用c语言画出五子棋棋盘

************************************************************** C++语言五子棋源程序 ************************************************************* #include <graphics.h>
#include <stdio.h>
#include <stdlib.h>
#include <dos.h>
#define backcolor CYAN
#define defaultcolor BLACK
#define linecolor MAGENTA
#define player1_color RED
#define player2_color WHITE
#define error_color RED
#define winner_color RED

const int left=40;
const int top=390;
const int d=30;
const int line_num=9;
const int turn=0;
const int r=d/3;
const int j=10;
int x,y,k=1,step=(line_num+1)*(line_num+1);
union REGS regs1,regs2;
class player1;
class player2;
class qipan{
public:
qipan();
~qipan(){};
void init_qipan();
friend void fall(player1 &num1,player2 &num2,qipan &num);
friend void input(player1 &num1,player2 &num2,qipan &num);