用c语言做贪吃射游戏怎么写 要写的思路和程序

#define N 200/*定义全局常量*/
#define m 25
#include <graphics.h>
#include <math.h>
#include <stdlib.h>
#include <dos.h>
#define LEFT 0x4b00
#define RIGHT 0x4d00
#define DOWN 0x5000
#define UP 0x4800
#define Esc 0x011b
int i,j,key,k;
struct Food/*构造食物结构体*/
{
int x;
int y;
int yes;
}food;
struct Goods/*构造宝贝结构体*/
{
int x;
int y;
int yes;
}goods;
struct Block/*构造障碍物结构体*/
{
int x[m];
int y[m];
int yes;
}block;
struct Snake{/*构造蛇结构体*/
int x[N];
int y[N];
int node;
int direction;
int life;
}snake;
struct Game/*构建游戏级别参数体*/
{
int score;
int level;
int speed;
}game;
/*定义函数*/
void init(void);/*定义图形驱动*/
void close(void);/*定义关闭函数*/
void drawk(void);/*定义界面函数*/
void gameover(void);/*定义游戏结束函数*/
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