一. 游戏效果
贪吃蛇
二. 游戏背景
贪吃蛇是久负盛名的游戏,它也和俄罗斯⽅块,扫雷等游戏位列经典游戏的⾏列。
贪吃蛇起源于1977年的投币式墙壁游戏《Blockade》,后移植到各种平台上。具体如下:
起源。1977年,投币式墙壁游戏生产商Gremlin推出了经典的街机游戏《Blockade》,两名玩家要分别控制角色移动,角色会不停长大,而且走过的地方会变成围栏,谁先碰到围栏或碰到自己的身体就算输。
起源。1977年,投币式墙壁游戏生产商Gremlin推出了经典的街机游戏《Blockade》,两名玩家要分别控制角色移动,角色会不停长大,而且走过的地方会变成围栏,谁先碰到围栏或碰到自己的身体就算输。
贪吃蛇最初的版本是像素版本,后来又衍生出3D版本、多人对战版本等2 3。
三、游戏开发日志
四、知识准备
本次实现贪吃蛇会使⽤到的⼀些Win32 API知识,那么就学习⼀下
4.1 Win32 API
Windows 这个多作业系统除了协调应⽤程序的执⾏、分配内存、管理资源之外, 它同时也是⼀个很⼤的服务中⼼,调⽤这个服务中⼼的各种服务(每⼀种服务就是⼀个函数),可以帮应⽤程式达到开启 视窗、描绘图形、使⽤周边设备等⽬的,由于这些函数服务的对象是应⽤程序(Application), 所以便 称之为 Application Programming Interface, 简称 API 函数。 WIN32 API也就是Microsoft Windows 32位平台的应⽤程序编程接⼝。
4.2 控制台程序
平常我们运⾏起来的⿊框程序其实就是控制台程序。
我们可以使⽤cmd命令来设置控制台窗⼝的⻓宽,也可以通过命令设置控制台窗⼝的名字:
设置控制台窗⼝的⼤⼩,30⾏,100列,设置控制台窗⼝的名字。
//控制台窗口设置
system("mode con cols=100 lines=35");
system("title 贪吃蛇");
4.3 控制台屏幕上的坐标COORD
COORD 是Windows API中定义的⼀种结构,表⽰⼀个字符在控制台屏幕上的坐标
typedef struct _COORD {
SHORT X;
SHORT Y;
} COORD, *PCOORD;
4.4 GetStdHandle
GetStdHandle是⼀个Windows API函数。它⽤于从⼀个特定的标准设备(标准输⼊、标准输出或标准错误)中取得⼀个句柄(⽤来标识不同设备的数值),使⽤这个句柄可以操作设备。
HANDLE hOutput = NULL;
//获取标准输出的句柄(⽤来标识不同设备的数值)
hOutput = GetStdHandle(STD_OUTPUT_HANDLE);
4.5 GetConsoleCursorInfo
检索有关指定控制台屏幕缓冲区的光标⼤⼩和可⻅性的信息
HANDLE hOutput = NULL;
//获取标准输出的句柄(⽤来标识不同设备的数值)
hOutput = GetStdHandle(STD_OUTPUT_HANDLE);
CONSOLE_CURSOR_INFO CursorInfo;
GetConsoleCursorInfo(hOutput, &CursorInfo);//获取控制台光标信息
4.5.1 CONSOLE_CURSOR_INFO
这个结构体,包含有关控制台游标的信息
typedef struct _CONSOLE_CURSOR_INFO {
DWORD dwSize;
BOOL bVisible;
} CONSOLE_CURSOR_INFO, *PCONSOLE_CURSOR_INFO;
(1) dwSize,由光标填充的字符单元格的百分⽐。 此值介于1到100之间。 光标外观会变化,范围从完全填充单元格到单元底部的⽔平线条。(2) bVisible,游标的可⻅性。 如果光标可⻅,则此成员为 TRUE。
CursorInfo.bVisible = false; //隐藏控制台光标
5.6 SetConsoleCursorInfo
设置指定控制台屏幕缓冲区的光标的⼤⼩和可⻅性。
HANDLE hOutput = GetStdHandle(STD_OUTPUT_HANDLE);
//影藏光标操作
CONSOLE_CURSOR_INFO CursorInfo;
GetConsoleCursorInfo(hOutput, &CursorInfo);//获取控制台光标信息
CursorInfo.bVisible = false; //隐藏控制台光标
SetConsoleCursorInfo(hOutput, &CursorInfo);//设置控制台光标状态
5.7 SetConsoleCursorPosition
设置指定控制台屏幕缓冲区中的光标位置,我们将想要设置的坐标信息放在COORD类型的pos中,调 ⽤SetConsoleCursorPosition函数将光标位置设置到指定的位置。COORD pos = { 10, 5}; HANDLE hOutput = NULL; //获取标准输出的句柄(⽤来标识不同设备的数值) hOutput = GetStdHandle(STD_OUTPUT_HANDLE); //设置标准输出上光标的位置为pos SetConsoleCursorPosition(hOutput, pos);
温馨提示:
这里我们可以将SetPos:封装⼀个设置光标位置的函数
//设置光标的坐标
void SetPos(short x, short y)
{
COORD pos = { x, y };
HANDLE hOutput = NULL;
//获取标准输出的句柄(⽤来标识不同设备的数值)
hOutput = GetStdHandle(STD_OUTPUT_HANDLE);
//设置标准输出上光标的位置为pos
SetConsoleCursorPosition(hOutput, pos);
}
5.8 GetAsyncKeyState
获取按键情况,将键盘上每个键的虚拟键值传递给函数,函数通过返回值来分辨按键的状态。返回值是short类型,在上⼀次调⽤ GetAsyncKeyState 函数后,如果 返回的16位的short数据中,最⾼位是1,说明按键的状态是按下,如果最⾼是0,说明按键的状态是抬起;如果最低位被置为1则说明,该按键被按过,否则为0。
如果我们要判断⼀个键是否被按过,可以检测GetAsyncKeyState返回值的最低值是否为1.
我们这里定义一个宏:
#define KEY_PRESS(VK) ( (GetAsyncKeyState(VK) & 0x1) ? 1 : 0 )
5.9 宽字符打印
在游戏地图上,我们打印墙体使⽤宽字符:□,打印蛇使⽤宽字符●,打印⻝物使⽤宽字符■
普通的字符是占⼀个字节的,这类宽字符是俩个字节。
5.9.1 setlocale函数
char* setlocale (int category, const char* locale);
setlocale 函数⽤于修改当前地区,可以针对⼀个类项修改,也可以针对所有类项。 setlocale 的第⼀个参数如果是LC_ALL,就会影响所有的类项。
C标准给第⼆个参数仅定义了2种可能取值:"C"和" "。
在任意程序执⾏开始,都会隐藏式执⾏调⽤:
setlocale(LC_ALL, "C");
当地区设置为"C"时,库函数按正常⽅式执⾏.
当地区设置为" "时,这种模式下程序会适应本地环境。⽐如:切换到我们的本地模式后就⽀
持宽字符(汉字)的输出等。
setlocale(LC_ALL, " ");//切换到本地环境
宽字符的打印如下:
#include <stdio.h>
#include<locale.h>
int main() {
setlocale(LC_ALL, "");
wchar_t ch1 = L'●';
wprintf(L"%c\n", ch1);
return 0;
}
五、游戏实现
5.1 游戏逻辑主体
#define _CRT_SECURE_NO_WARNINGS
#include"snake.h"
#include<locale.h>
#include<stdio.h>
int main()
{char ch;setlocale(LC_ALL, "");//切换到本地环境,支持宽字符srand((unsigned int)time(NULL));do{Snake snake = { 0 };GameInit(&snake);GameRun(&snake);GameOver(&snake);printf("小垃圾还要再来吗?是:Y,否:N\n");ch = getchar();getchar();} while (ch == 'y' || ch == 'Y');return 0;
}
5.2 游戏初始化实现
#define _CRT_SECURE_NO_WARNINGS
#include"snake.h"#define WALL L'□'
#define BODY L'●'
#define FOOD L'█'
void SetPos(short x, short y)
{COORD pos = { x, y };HANDLE hOutput = NULL;//获取标准输出的句柄(⽤来标识不同设备的数值)hOutput = GetStdHandle(STD_OUTPUT_HANDLE);//设置标准输出上光标的位置为posSetConsoleCursorPosition(hOutput, pos);
}
void WelcomeToGame()
{SetPos(40, 13);printf("欢迎来到贪吃蛇小游戏");SetPos(42, 22);system("pause");//会显示按任意键继续的信息,按任意键后继续执行下一步system("cls");SetPos(25, 12);printf("↑ . ↓ . ← . → 分别控制蛇的移动, F3为加速,F4为减速\n");SetPos(42, 22);system("pause");//会显示按任意键继续的信息,按任意键后继续执行下一步system("cls");/*getchar();*/}
void CreateMap()
{SetPos(0,0);int i = 0;for(i=0;i<58;i=i+2){wprintf(L"%c", WALL);}SetPos(0, 26);for (i = 0; i < 58; i = i + 2){wprintf(L"%c", WALL);}for (i = 1; i <26; i++){SetPos(0, i);wprintf(L"%c", WALL);}for (i = 1; i < 26; i++){SetPos(56, i);wprintf(L"%c", WALL);}/*getchar();*/
}void InitSnake(Snake* snake)
{//初始化蛇身for (int i = 0; i < 5; i++){SnakeNode* node = (SnakeNode*)malloc(sizeof(SnakeNode));node->x = 24 + 2 * i;node->y = 15;node->next = NULL;if (snake->pSnake== NULL){snake->pSnake= node;}else{node->next = snake->pSnake;snake->pSnake = node;}}SnakeNode* cur = snake->pSnake;while (cur){int x = cur->x;int y = cur->y;SetPos(x, y);wprintf(L"%c", BODY);cur = cur->next;}snake->status = RUN;snake->dir = RIGHT;snake->FoodWeight = 10;snake->pFood = NULL;snake->score = 0;snake->SleepTime = 200;
}
void CreateFood(Snake* snake)
{int x = 0;int y = 0;again:do{x = rand() % 53 + 2;y = rand() % 24 + 1;} while (x % 2 != 0);SnakeNode* cur = snake->pSnake;do{if (x == cur->x && y == cur->y){goto again;}cur = cur->next;} while (cur);SnakeNode* food = (SnakeNode*)malloc(sizeof(SnakeNode));food->x = x;food->y = y;snake->pFood = food;SetPos(x, y);wprintf(L"%c", FOOD);/*getchar();*/}void GameInit(Snake* snake)
{//控制台窗口设置system("mode con cols=100 lines=35");system("title 贪吃蛇");//隐藏光标HANDLE hOutput = GetStdHandle(STD_OUTPUT_HANDLE);CONSOLE_CURSOR_INFO CursorInfo;GetConsoleCursorInfo(hOutput, &CursorInfo);//获取控制台光标信息CursorInfo.bVisible = false; //隐藏控制台光标SetConsoleCursorInfo(hOutput, &CursorInfo);//设置控制台光标状态//打印欢迎界面WelcomeToGame();//创建地图CreateMap();//初始化贪吃蛇InitSnake(snake);//创建食物CreateFood(snake);
}
5.3 游戏运行实现
void PrintHelpInfo()
{SetPos(60, 13);printf("1. 不能穿墙不能咬到自己\n");SetPos(60, 14);printf("2.↑.↓.←.→分别控制蛇的移动\n");SetPos(60, 15);printf("3. F3为加速,F4为减速\n");SetPos(60, 16);printf("4. ESC-退出,空格-暂停\n");
}void Pause()
{while (1){Sleep(200);if (KEY_PRESS(VK_SPACE) == 1){break;}}}
void EatFood(Snake* snake, SnakeNode* snakenext)
{snakenext->next = snake->pSnake;snake->pSnake = snakenext;SnakeNode* cur = snake->pSnake;while (cur){SetPos(cur->x, cur->y);wprintf(L"%lc", BODY);cur = cur->next;}free(snake->pFood);snake->pFood = NULL;CreateFood(snake);}
void NoEatFood(Snake* snake, SnakeNode* snakenext)
{snakenext->next = snake->pSnake;snake->pSnake = snakenext;SnakeNode* cur = snake->pSnake;while (cur->next->next){SetPos(cur->x, cur->y);wprintf(L"%lc", BODY);cur = cur->next;}SetPos(cur->x, cur->y);wprintf(L"%lc", BODY);SetPos(cur->next->x, cur->next->y);printf(" ");free(cur->next);cur->next = NULL;
}void SnakeMove(Snake* snake)
{SnakeNode* snakenext = (SnakeNode*)malloc(sizeof(SnakeNode));if (snake->dir == UP){snakenext->x = snake->pSnake->x;snakenext->y = snake->pSnake->y -1;snakenext->next = NULL;}else if (snake->dir == DOWN){snakenext->x = snake->pSnake->x;snakenext->y = snake->pSnake->y +1;snakenext->next = NULL;}if (snake->dir == LEFT){snakenext->x = snake->pSnake->x-2;snakenext->y = snake->pSnake->y ;snakenext->next = NULL;}if (snake->dir == RIGHT){snakenext->x = snake->pSnake->x + 2;snakenext->y = snake->pSnake->y;snakenext->next = NULL;}//判断下一个节点是否为食物if (snakenext->x == snake->pFood->x && snakenext->y == snake->pFood->y){EatFood(snake,snakenext);//吃食物snake->score += snake->FoodWeight;}else{NoEatFood(snake,snakenext);//不吃食物}//碰撞检测if (snake->pSnake->x == 0 || snake->pSnake->x == 56 || snake->pSnake->y == 0 || snake->pSnake->y == 26){snake->status = KILL_BY_WALL;}SnakeNode* cur = snake->pSnake->next;while (cur){if (cur->x == snake->pSnake->x && cur->y == snake->pSnake->y){snake->status = KILL_BY_SELF;}cur = cur->next;}
}void GameRun(Snake* snake)
{//打印帮助信息PrintHelpInfo();do{SetPos(60, 8);printf("游戏总得分:%5d ", snake->score);SetPos(60, 9);printf("每个食物的分数:%2d ", snake->FoodWeight);if (KEY_PRESS(VK_UP) == 1&&snake->dir!=DOWN){snake->dir = UP;}else if (KEY_PRESS(VK_DOWN) == 1 && snake->dir != UP){snake->dir = DOWN;}else if (KEY_PRESS(VK_RIGHT) == 1 && snake->dir != LEFT){snake->dir = RIGHT;}else if (KEY_PRESS(VK_LEFT) == 1 && snake->dir != RIGHT){snake->dir =LEFT;}else if (KEY_PRESS(VK_F3) == 1){if (snake->SleepTime>=80){snake->SleepTime -= 30;snake->FoodWeight += 2;}}else if (KEY_PRESS(VK_F4) == 1){if (snake->SleepTime<=320){snake->SleepTime += 30;snake->FoodWeight -= 2;}}else if (KEY_PRESS(VK_ESCAPE) == 1){snake->status = OVER;break;}else if (KEY_PRESS(VK_SPACE) == 1){Pause();}SnakeMove(snake);Sleep(snake->SleepTime);//每一帧停0.2s} while (snake->status==RUN);
}
5.4 游戏结束实现
void GameOver(Snake* snake)
{switch (snake->status){case KILL_BY_WALL:SetPos(20, 15);printf("你已经撞墙了,小垃圾!\n");break;case KILL_BY_SELF:SetPos(20, 15);printf("你已经自杀了,小垃圾!\n");break;case OVER:SetPos(20, 15);printf("你退出游戏了,小垃圾!\n");break;}SetPos(0, 29);}
六、 完整代码
6.1 snake.h
#define _CRT_SECURE_NO_WARNINGS
#include<stdbool.h>
#include<stdio.h>
#include<windows.h>
#include<stdlib.h>
#include<time.h>
#define KEY_PRESS(VK) ( (GetAsyncKeyState(VK) & 0x1) ? 1 : 0 )
enum direction{UP = 1, DOWN, LEFT, RIGHT};//蛇的方向
enum game_status{RUN,KILL_BY_WALL,KILL_BY_SELF,OVER};typedef struct SnakeNode
{int x;int y;struct SnakeNode* next;
}SnakeNode;typedef struct Snake
{SnakeNode* pSnake;//指向贪吃蛇头节点SnakeNode* pFood;//指向食物的节点int score;int FoodWeight;int SleepTime;enum direction dir;//蛇的方向enum game_status status;//游戏状态
}Snake;
void GameInit(Snake*snake);
void WelcomeToGame();
void CreateMap();
void InitSnake(Snake* snake);
void CreateFood(Snake* snake);
void GameRun(Snake* snake);
void PrintHelpInfo();
void Pause();
void SnakeMove(Snake* snake);void EatFood(Snake* snake,SnakeNode*snakenext);
void NoEatFood(Snake* snake, SnakeNode* snakenext);
void GameOver(Snake* snake);
6.2 snake.c
#define _CRT_SECURE_NO_WARNINGS
#include"snake.h"#define WALL L'□'
#define BODY L'●'
#define FOOD L'█'
void SetPos(short x, short y)
{COORD pos = { x, y };HANDLE hOutput = NULL;//获取标准输出的句柄(⽤来标识不同设备的数值)hOutput = GetStdHandle(STD_OUTPUT_HANDLE);//设置标准输出上光标的位置为posSetConsoleCursorPosition(hOutput, pos);
}
void WelcomeToGame()
{SetPos(40, 13);printf("欢迎来到贪吃蛇小游戏");SetPos(42, 22);system("pause");//会显示按任意键继续的信息,按任意键后继续执行下一步system("cls");SetPos(25, 12);printf("↑ . ↓ . ← . → 分别控制蛇的移动, F3为加速,F4为减速\n");SetPos(42, 22);system("pause");//会显示按任意键继续的信息,按任意键后继续执行下一步system("cls");/*getchar();*/}
void CreateMap()
{SetPos(0,0);int i = 0;for(i=0;i<58;i=i+2){wprintf(L"%c", WALL);}SetPos(0, 26);for (i = 0; i < 58; i = i + 2){wprintf(L"%c", WALL);}for (i = 1; i <26; i++){SetPos(0, i);wprintf(L"%c", WALL);}for (i = 1; i < 26; i++){SetPos(56, i);wprintf(L"%c", WALL);}/*getchar();*/
}void InitSnake(Snake* snake)
{//初始化蛇身for (int i = 0; i < 5; i++){SnakeNode* node = (SnakeNode*)malloc(sizeof(SnakeNode));node->x = 24 + 2 * i;node->y = 15;node->next = NULL;if (snake->pSnake== NULL){snake->pSnake= node;}else{node->next = snake->pSnake;snake->pSnake = node;}}SnakeNode* cur = snake->pSnake;while (cur){int x = cur->x;int y = cur->y;SetPos(x, y);wprintf(L"%c", BODY);cur = cur->next;}snake->status = RUN;snake->dir = RIGHT;snake->FoodWeight = 10;snake->pFood = NULL;snake->score = 0;snake->SleepTime = 200;
}
void CreateFood(Snake* snake)
{int x = 0;int y = 0;again:do{x = rand() % 53 + 2;y = rand() % 24 + 1;} while (x % 2 != 0);SnakeNode* cur = snake->pSnake;do{if (x == cur->x && y == cur->y){goto again;}cur = cur->next;} while (cur);SnakeNode* food = (SnakeNode*)malloc(sizeof(SnakeNode));food->x = x;food->y = y;snake->pFood = food;SetPos(x, y);wprintf(L"%c", FOOD);/*getchar();*/}void GameInit(Snake* snake)
{//控制台窗口设置system("mode con cols=100 lines=35");system("title 贪吃蛇");//隐藏光标HANDLE hOutput = GetStdHandle(STD_OUTPUT_HANDLE);CONSOLE_CURSOR_INFO CursorInfo;GetConsoleCursorInfo(hOutput, &CursorInfo);//获取控制台光标信息CursorInfo.bVisible = false; //隐藏控制台光标SetConsoleCursorInfo(hOutput, &CursorInfo);//设置控制台光标状态//打印欢迎界面WelcomeToGame();//创建地图CreateMap();//初始化贪吃蛇InitSnake(snake);//创建食物CreateFood(snake);
}void PrintHelpInfo()
{SetPos(60, 13);printf("1. 不能穿墙不能咬到自己\n");SetPos(60, 14);printf("2.↑.↓.←.→分别控制蛇的移动\n");SetPos(60, 15);printf("3. F3为加速,F4为减速\n");SetPos(60, 16);printf("4. ESC-退出,空格-暂停\n");
}void Pause()
{while (1){Sleep(200);if (KEY_PRESS(VK_SPACE) == 1){break;}}}
void EatFood(Snake* snake, SnakeNode* snakenext)
{snakenext->next = snake->pSnake;snake->pSnake = snakenext;SnakeNode* cur = snake->pSnake;while (cur){SetPos(cur->x, cur->y);wprintf(L"%lc", BODY);cur = cur->next;}free(snake->pFood);snake->pFood = NULL;CreateFood(snake);}
void NoEatFood(Snake* snake, SnakeNode* snakenext)
{snakenext->next = snake->pSnake;snake->pSnake = snakenext;SnakeNode* cur = snake->pSnake;while (cur->next->next){SetPos(cur->x, cur->y);wprintf(L"%lc", BODY);cur = cur->next;}SetPos(cur->x, cur->y);wprintf(L"%lc", BODY);SetPos(cur->next->x, cur->next->y);printf(" ");free(cur->next);cur->next = NULL;
}void SnakeMove(Snake* snake)
{SnakeNode* snakenext = (SnakeNode*)malloc(sizeof(SnakeNode));if (snake->dir == UP){snakenext->x = snake->pSnake->x;snakenext->y = snake->pSnake->y -1;snakenext->next = NULL;}else if (snake->dir == DOWN){snakenext->x = snake->pSnake->x;snakenext->y = snake->pSnake->y +1;snakenext->next = NULL;}if (snake->dir == LEFT){snakenext->x = snake->pSnake->x-2;snakenext->y = snake->pSnake->y ;snakenext->next = NULL;}if (snake->dir == RIGHT){snakenext->x = snake->pSnake->x + 2;snakenext->y = snake->pSnake->y;snakenext->next = NULL;}//判断下一个节点是否为食物if (snakenext->x == snake->pFood->x && snakenext->y == snake->pFood->y){EatFood(snake,snakenext);//吃食物snake->score += snake->FoodWeight;}else{NoEatFood(snake,snakenext);//不吃食物}//碰撞检测if (snake->pSnake->x == 0 || snake->pSnake->x == 56 || snake->pSnake->y == 0 || snake->pSnake->y == 26){snake->status = KILL_BY_WALL;}SnakeNode* cur = snake->pSnake->next;while (cur){if (cur->x == snake->pSnake->x && cur->y == snake->pSnake->y){snake->status = KILL_BY_SELF;}cur = cur->next;}
}void GameRun(Snake* snake)
{//打印帮助信息PrintHelpInfo();do{SetPos(60, 8);printf("游戏总得分:%5d ", snake->score);SetPos(60, 9);printf("每个食物的分数:%2d ", snake->FoodWeight);if (KEY_PRESS(VK_UP) == 1&&snake->dir!=DOWN){snake->dir = UP;}else if (KEY_PRESS(VK_DOWN) == 1 && snake->dir != UP){snake->dir = DOWN;}else if (KEY_PRESS(VK_RIGHT) == 1 && snake->dir != LEFT){snake->dir = RIGHT;}else if (KEY_PRESS(VK_LEFT) == 1 && snake->dir != RIGHT){snake->dir =LEFT;}else if (KEY_PRESS(VK_F3) == 1){if (snake->SleepTime>=80){snake->SleepTime -= 30;snake->FoodWeight += 2;}}else if (KEY_PRESS(VK_F4) == 1){if (snake->SleepTime<=320){snake->SleepTime += 30;snake->FoodWeight -= 2;}}else if (KEY_PRESS(VK_ESCAPE) == 1){snake->status = OVER;break;}else if (KEY_PRESS(VK_SPACE) == 1){Pause();}SnakeMove(snake);Sleep(snake->SleepTime);//每一帧停0.2s} while (snake->status==RUN);
}void GameOver(Snake* snake)
{switch (snake->status){case KILL_BY_WALL:SetPos(20, 15);printf("你已经撞墙了,小垃圾!\n");break;case KILL_BY_SELF:SetPos(20, 15);printf("你已经自杀了,小垃圾!\n");break;case OVER:SetPos(20, 15);printf("你退出游戏了,小垃圾!\n");break;}SetPos(0, 29);}
6.3 text.c
#define _CRT_SECURE_NO_WARNINGS
#include"snake.h"
#include<locale.h>
#include<stdio.h>
int main()
{char ch;setlocale(LC_ALL, "");//切换到本地环境,支持宽字符srand((unsigned int)time(NULL));do{Snake snake = { 0 };GameInit(&snake);GameRun(&snake);GameOver(&snake);printf("小垃圾还要再来吗?是:Y,否:N\n");ch = getchar();getchar();} while (ch == 'y' || ch == 'Y');return 0;
}