程序代码：

while(flag==1)
            {
                if(t>5)
                    break;

                flag=0;

                pt=head;
                while(pt!=NULL)
                {
                    if(food.x==pt->x && food.y==pt->y)
                    {
                        flag=1;
                        food.x=rand()%15;
                        food.y=rand()%15;
                        break;
                    }
                    pt=pt->next;
                }
                t++;
            }
            if(t>5)
            {
                if(c=='d')
                {
                    food.x=head->x+1;
                    food.y=head->y;
                    if(food.x>=15)
                        food.x-=15;
                }
                else if(c=='a')
                {
                    food.x=head->x-1;
                    food.y=head->y;
                    if(food.x<0)
                        food.x+=15;
                }
                else if(c=='w')
                {
                    food.x=head->x;
                    food.y=head->y+1;
                    if(food.y>=15)
                        food.y-=15;
                }
                else if(c=='s')
                {
                    food.x=head->x;
                    food.y=head->y-1;
                    if(food.y<0)
                        food.y+=15;
                }
            }
        }

        if(kbhit())
        {
            c1=getch();
            if(c1==27)
                break;
           
            if(c!='d' && c1=='a')
                c=c1;
            else if(c!='a' && c1=='d')
                c=c1;
            else if(c!='w' && c1=='s')
                c=c1;
            else if(c!='s' && c1=='w')
                c=c1;
        }

        pt=rear;
        while(pt!=head )
        {
            pt->x=pt->pre->x;
            pt->y=pt->pre->y;
            pt=pt->pre;
        }

        if(c=='d')
        {
            head->y+=1;
            if(head->y>=15)
                head->y-=15;
        }
        else if(c=='a')
        {
            head->y-=1;
            if(head->y<0)
                head->y+=15;
        }
        else if(c=='w')
        {
            head->x-=1;
            if(head->x<0)
                head->x+=15;
        }
        else if(c=='s')
        {
            head->x+=1;
            if(head->x>=15)
                head->x-=15;
        }

        pt=head->next;
        while(pt!=NULL)
        {
            if(head->x==pt->x && head->y==pt->y)
            {
                gameover=1;
                break;
            }
            pt=pt->next ;
        }
        if(gameover==1)
            break;
       
        system("cls");
        printf("  ───────────────\n");
        for(i=0;i<15;i++)
        {
            printf("│");
            for(j=0;j<15;j++)
            {

                flag=0;
                pt=head;
                while(pt!=NULL)
                {
                    if(i==pt->x && j==pt->y)
                    {
                        if(pt==head)
                            printf("■");
                        else
                            printf("□");
                        flag=1;
                        break;
                    }
                    pt=pt->next;
                }


                if(flag==0)
                {
                    if(i==food.x && j==food.y)
                    {
                        putchar(food.c);
                        putchar(food.c);
                        continue;
                    }
                    printf("  ");
                }
            }
            printf("│");
            putchar('\n');
        }
        printf("  ───────────────\n");
       
        _sleep(200);   
    }

    if(gameover==1)
        puts("game over!\n");

    getch();
} 

程序代码：

while(flag==1)
            {
                if(t>5)
                    break;

                flag=0;

                pt=head;
                while(pt!=NULL)
                {
                    if(food.x==pt->x && food.y==pt->y)
                    {
                        flag=1;
                        food.x=rand()%15;
                        food.y=rand()%15;
                        break;
                    }
                    pt=pt->next;
                }
                t++;
            }
            if(t>5)
            {
                if(c=='d')
                {
                    food.x=head->x+1;
                    food.y=head->y;
                    if(food.x>=15)
                        food.x-=15;
                }
                else if(c=='a')
                {
                    food.x=head->x-1;
                    food.y=head->y;
                    if(food.x<0)
                        food.x+=15;
                }
                else if(c=='w')
                {
                    food.x=head->x;
                    food.y=head->y+1;
                    if(food.y>=15)
                        food.y-=15;
                }
                else if(c=='s')
                {
                    food.x=head->x;
                    food.y=head->y-1;
                    if(food.y<0)
                        food.y+=15;
                }
            }
        }

        if(kbhit())
        {
            c1=getch();
            if(c1==27)
                break;
          
            if(c!='d' && c1=='a')
                c=c1;
            else if(c!='a' && c1=='d')
                c=c1;
            else if(c!='w' && c1=='s')
                c=c1;
            else if(c!='s' && c1=='w')
                c=c1;
        }

程序代码：

    while(flag==1)
    {
        if(t>5)    //定义不明确，功能不了解，猜测初始值为0，检测食物是否连续5次出现在蛇身
            break;
   
        flag=0;
   
        pt=head;//将指针指向蛇头
        while(pt!=NULL)
        {    //检测食物是否在蛇身上
            if(food.x==pt->x && food.y==pt->y)
            {    //食物在蛇身上
                flag=1;        //置flag为 1，使while(flag==1)成立，再次从蛇头判断
                food.x=rand()%15;    //重新生成食物
                food.y=rand()%15;
                break;
            }
            pt=pt->next;//检测下一节蛇身
        }
        t++;
    }
    if(t>5)
    {
        if(c=='d')
        {    //上面的食物连续 5次出现在蛇身，直接将食物，放在蛇头旁边
            food.x=head->x+1;
            food.y=head->y;
            if(food.x>=15)    //15可能是边界，食物出边界时食物出现在对面边界
                food.x-=15;
        }
        else if(c=='a')
        {
            food.x=head->x-1;
            food.y=head->y;
            if(food.x<0)
                food.x+=15;
        }
        else if(c=='w')
        {
            food.x=head->x;
            food.y=head->y+1;
            if(food.y>=15)
                food.y-=15;
        }
        else if(c=='s')
        {
            food.x=head->x;
            food.y=head->y-1;
            if(food.y<0)
                food.y+=15;
        }
    }
}
if(kbhit())    //若有键盘输入
{
    c1=getch();//获取输入信息
    if(c1==27)    //ESC直接退出
        break;

    if(c!='d' && c1=='a')
        c=c1;
    else if(c!='a' && c1=='d')
        c=c1;
    else if(c!='w' && c1=='s')
        c=c1;
    else if(c!='s' && c1=='w')
        c=c1;
}