程序代码：

#include<graphics.h>
#include<stdio.h>
#include<conio.h>
#include<windows.h>
#define N 28
void PlayGame();
int GameOver1(int chess[N][N],int flag);
void BackGround()
{
    IMAGE GameBackground;

/*    loadimage(&GameBackground,"GameBackground.jpg");

    int width=GameBackground.getwidth();
    int height=GameBackground.getheight();

    initgraph(width,height);
    putimage(0,0,&GameBackground);*/

    setlinecolor(BLACK);

    for (int i=20;i<=540;i+=20)
    {
        line(20,i,540,i);
        line(i,20,i,540);
    }

    setfillcolor(BLACK);

    fillcircle(100,280,2);
    fillcircle(280,100,2);

    fillcircle(460,100,2);
    fillcircle(100,460,2);

    fillcircle(460,460,2);
    fillcircle(100,100,2);

    fillcircle(460,280,2);
    fillcircle(280,460,2);

    fillcircle(280,280,2);
}
void messagebox()
{
    setlinecolor(BLACK);
    setfillcolor(RGB(255,201,14));
    fillrectangle(540,20,720,190);//左上角和右下角参数,确定一个矩形
    settextstyle(50,28,"黑体");    //画提示框里面的内容
    setbkmode(TRANSPARENT);//字体不背景透明处理

    setlinecolor(BLACK);
    settextcolor(BLACK);
    outtextxy(550,50,"黑棋");
    setfillcolor(BLACK);
    fillcircle(680,75,15);

    setlinecolor(WHITE);
    settextcolor(WHITE);
    outtextxy(550,110,"白棋");
    setfillcolor(WHITE);
    fillcircle(680,135,15);

    PlayGame();

    getchar();
    getchar();

}
void PlayGame()
{
    //鼠标
    int x,y,i,j;

    int chess[N][N]={0};

    MOUSEMSG m;
    while (1)
    {
        m=GetMouseMsg();
        switch(m.uMsg)
        {
            case WM_LBUTTONDOWN:

                if (m.x>=20&&m.x<=540&&m.y>=20&&m.y<=540)
                {
                    x=m.x%20;
                    if (x<=10)
                        m.x=m.x-x;
                    else
                        m.x=m.x-x+20;

                    y=m.y%20;
                    if (y<=10)
                        m.y=m.y-y;
                    else
                        m.y=m.y-y+20;

                    i=m.x/20;
                    j=m.y/20;
                    if (chess[i][j]!=0)
                        continue;

                    setlinecolor(BLACK);
                    setfillcolor(BLACK);
                    fillcircle(m.x,m.y,8);
                    chess[i][j]=1;

                    if (GameOver1(chess,1)==1)
                    {
                        settextcolor(RED);
                        settextstyle(50,50,"黑体");
                        outtextxy(100,200,"这局黑棋胜利");
                    }
                }
                break;

              case WM_RBUTTONDOWN:

                if (m.x>=20&&m.x<=550&&m.y>=20&&m.y<=550)
                {
                    x=m.x%20;
                    if (x<=10)
                        m.x=m.x-x;
                    else
                        m.x=m.x-x+20;

                    y=m.y%20;
                    if (y<=10)
                        m.y=m.y-y;
                    else
                        m.y=m.y-y+20;

                    i=m.x/20;
                    j=m.y/20;
                    if (chess[i][j]!=0)
                        continue;

                    setlinecolor(WHITE);
                    setfillcolor(WHITE);
                    fillcircle(m.x,m.y,8);

                    chess[i][j]=2;
                    if (GameOver1(chess,2)==1)
                    {
                        settextcolor(WHITE);
                        settextstyle(50,50,"黑体");
                        outtextxy(100,200,"这局白棋胜利");
                    }
                }
                break;
        }
    }
}
int GameOver1(int chess[N][N],int flag)
{
    int i,j,k,low,row,tilt1,tilt2;
    for (i=0;i<N;i++)
    {
        for (k=0;k<N-4;k++)
        {
            low=row=tilt1=tilt2=0;
            for (j=k;j<k+5;j++)
            {
                if (chess[i][j]==flag)
                    low++;
                if (chess[j][i]==flag)
                    row++;
                if (chess[i+(j-k)][j]==flag)
                    tilt1++;
                if (chess[i+4-(j-k)][j]==flag)
                    tilt2++;
            }
            if (low==5||row==5||tilt1==5||tilt2==5)
                return 1;
        }
    }

    return 0;
}
int main()
{
    initgraph(750,560);
    
    setbkcolor(RGB(255,100,0));
    cleardevice();

    BackGround();
    messagebox();

    getch();
    closegraph();

    return 0;
}