• 加了getchar()主要作用是使程序在结束之前暂停，等待用户输入。这在终端应用程序中尤其有用，因为它防止程序运行完毕后立即关闭，让用户有时间查看屏幕上的输出结果。如果没有这个暂停，程序可能会迅速结束，特别是在命令行环境下，这会使你错过重要的调试信息或输出内容。

• 如果不加程序在完成绘制地图后会立即结束。如果你在命令行终端中运行程序，这可能导致你没有时间查看输出结果，因为程序会在瞬间完成执行并关闭。getchar() 让程序在结束之前暂停，给你时间查看输出。

void GameRun(pSnake ps)
{//打印右侧帮助信息PrintHelpInfo();do{SetPos(64, 10);printf("得分：%d ", ps->_Socre);printf("每个⻝物得分：%d分", ps->_foodWeight);if (KEY_PRESS(VK_UP) && ps->_Dir != DOWN){ps->_Dir = UP;}else if (KEY_PRESS(VK_DOWN) && ps->_Dir != UP){ps->_Dir = DOWN;}else if (KEY_PRESS(VK_LEFT) && ps->_Dir != RIGHT){ps->_Dir = LEFT;}else if (KEY_PRESS(VK_RIGHT) && ps->_Dir != LEFT){ps->_Dir = RIGHT;}else if (KEY_PRESS(VK_SPACE)){pause();}else if (KEY_PRESS(VK_ESCAPE)){ps->_Status = END_NOMAL;break;}else if (KEY_PRESS(VK_F3)){if (ps->_SleepTime >= 50){ps->_SleepTime -= 30;ps->_foodWeight += 2;}}else if (KEY_PRESS(VK_F4)){if (ps->_SleepTime < 350){ps->_SleepTime += 30;ps->_foodWeight -= 2;if (ps->_SleepTime == 350){ps->_foodWeight = 1;}}}//蛇每次⼀定之间要休眠的时间，时间短，蛇移动速度就快Sleep(ps->_SleepTime);SnakeMove(ps);} while (ps->_Status == OK);
}

7.3.1 KEY_PRESS

void SnakeMove(pSnake ps)
{//创建下⼀个节点pSnakeNode pNextNode = (pSnakeNode)malloc(sizeof(SnakeNode));if (pNextNode == NULL){perror("SnakeMove()::malloc()");return;}//确定下⼀个节点的坐标，下⼀个节点的坐标根据，蛇头的坐标和⽅向确定switch (ps->_Dir){case UP:{pNextNode->x = ps->_pSnake->x;pNextNode->y = ps->_pSnake->y - 1;}break;case DOWN:{pNextNode->x = ps->_pSnake->x;pNextNode->y = ps->_pSnake->y + 1;}break;case LEFT:{pNextNode->x = ps->_pSnake->x - 2;pNextNode->y = ps->_pSnake->y;}break;case RIGHT:{pNextNode->x = ps->_pSnake->x + 2;pNextNode->y = ps->_pSnake->y;}break;}//如果下⼀个位置就是⻝物if (NextIsFood(pNextNode, ps)){EatFood(pNextNode, ps);}else//如果没有⻝物{NoFood(pNextNode, ps);}KillByWall(ps);KillBySelf(ps);
}

7.3.3.1 NextIsFood

//pSnakeNode psn 是下⼀个节点的地址
//pSnake ps 维护蛇的指针
int NextIsFood(pSnakeNode psn, pSnake ps)
{return (psn->x == ps->_pFood->x) && (psn->y == ps->_pFood->y);
}

//pSnakeNode psn 是下⼀个节点的地址
//pSnake ps 维护蛇的指针
void EatFood(pSnakeNode psn, pSnake ps)
{//头插法psn->next = ps->_pSnake;ps->_pSnake = psn;pSnakeNode cur = ps->_pSnake;//打印蛇while (cur){SetPos(cur->x, cur->y);wprintf(L"%c", BODY);cur = cur->next;}ps->_Socre += ps->_foodWeight;//释放⻝物节点free(ps->_pFood);//创建新的⻝物CreateFood(ps);
}

 //pSnakeNode psn 是下⼀个节点的地址//pSnake ps 维护蛇的指针void NoFood(pSnakeNode psn, pSnake ps){//头插法psn->next = ps->_pSnake;ps->_pSnake = psn;pSnakeNode cur = ps->_pSnake;//打印蛇while (cur->next->next){SetPos(cur->x, cur->y);wprintf(L"%c", BODY);
cur = cur->next;}//最后⼀个位置打印空格，然后释放节点SetPos(cur->next->x, cur->next->y);printf(" ");free(cur->next);cur->next = NULL;
}

//pSnake ps 维护蛇的指针
int KillByWall(pSnake ps)
{if ((ps->_pSnake->x == 0)|| (ps->_pSnake->x == 56)|| (ps->_pSnake->y == 0)|| (ps->_pSnake->y == 26)){ps->_Status = KILL_BY_WALL;return 1;}return 0;
}

//pSnake ps 维护蛇的指针
int KillBySelf(pSnake ps)
{pSnakeNode cur = ps->_pSnake->next;while (cur){if ((ps->_pSnake->x == cur->x)&& (ps->_pSnake->y == cur->y)){ps->_Status = KILL_BY_SELF;return 1;}cur = cur->next;}return 0;
}

void GameEnd(pSnake ps)
{pSnakeNode cur = ps->_pSnake;SetPos(24, 12);switch (ps->_Status){case END_NOMAL:printf("您主动退出游戏\n");break;case KILL_BY_SELF:printf("您撞上⾃⼰了 ,游戏结束!\n");break;printf("您撞墙了,游戏结束!\n");break;}//释放蛇⾝的节点while (cur){pSnakeNode del = cur;cur = cur->next;free(del);}
}