写出贪吃蛇代码300行，包括数组，指针、结构体、文件

以下是一个使用数组、指针、结构体和文件的贪吃蛇代码，共300行：

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <conio.h>

#define MAX_X 40
#define MAX_Y 20
#define SNAKE_MAX_LENGTH 100

int map[MAX_Y][MAX_X]; //游戏地图
int snake_length; //蛇的长度
char direction; //蛇的方向
int score, max_score; //分数和最高分

typedef struct Point {
    int x, y;
} Point;

Point snake[SNAKE_MAX_LENGTH]; //蛇身

void init_map() { //初始化地图
    int i, j;
    for (i = 0; i < MAX_Y; i++) {
        for (j = 0; j < MAX_X; j++) {
            if (i == 0 || i == MAX_Y - 1 || j == 0 || j == MAX_X - 1) {
                map[i][j] = -1; //边界
            } else {
                map[i][j] = 0; //空地
            }
        }
    }
}

void draw_map() { //绘制地图
    int i, j;
    system("cls"); //清屏
    for (i = 0; i < MAX_Y; i++) {
        for (j = 0; j < MAX_X; j++) {
            switch (map[i][j]) {
                case -1: printf("#"); break; //边界
                case 0: printf(" "); break; //空地
                case 1: printf("*"); break; //蛇身
                case 2: printf("$"); break; //食物
            }
        }
        printf("\n");
    }
    printf("得分：%d  最高分：%d\n", score, max_score);
}

void init_snake() { //初始化蛇
    int i;
    snake_length = 3;
    for (i = 0; i < snake_length; i++) {
        snake[i].x = MAX_X / 2 - i;
        snake[i].y = MAX_Y / 2;
        map[snake[i].y][snake[i].x] = 1; //更新地图
    }
    direction = 'd'; //初始方向向右
}

void create_food() { //生成食物
    int x, y;
    do {
        x = rand() % (MAX_X - 2) + 1; //随机生成x坐标，不能在边界上
        y = rand() % (MAX_Y - 2) + 1; //随机生成y坐标，不能在边界上
    } while (map[y][x] != 0); //如果生成的位置不是空地，则重新生成
    map[y][x] = 2; //更新地图
}

void move_snake() { //移动蛇
    int i;
    Point new_head = {snake[0].x, snake[0].y};
    switch (direction) {
        case 'w': new_head.y--; break; //向上
        case 's': new_head.y++; break; //向下
        case 'a': new_head.x--; break; //向左
        case 'd': new_head.x++; break; //向右
    }
    if (map[new_head.y][new_head.x] == -1 || map[new_head.y][new_head.x] == 1) { //撞墙或咬到自己
        if (score > max_score) {
            max_score = score;
        }
        score = 0;
        init_map();
        init_snake();
        create_food();
        return;
    }
    if (new_head.x == food.x && new_head.y == food.y) { //吃到食物
        snake_length++;
        score += 10;
        create_food();
    } else { //移动蛇身
        map[snake[snake_length - 1].y][snake[snake_length - 1].x] = 0; //清除蛇尾
        for (i = snake_length - 1; i > 0; i--) { //蛇身向前移动
            snake[i] = snake[i - 1];
            map[snake[i].y][snake[i].x] = 1; //更新地图
        }
    }
    snake[0] = new_head;
    map[new_head.y][new_head.x] = 1; //更新地图
}

void save_game() { //保存游戏进度
    FILE *fp;
    int i;
    fp = fopen("snake.sav", "wb");
    fwrite(&snake_length, sizeof(int), 1, fp); //写入蛇的长度
    fwrite(&direction, sizeof(char), 1, fp); //写入蛇的方向
    fwrite(&score, sizeof(int), 1, fp); //写入分数
    fwrite(&max_score, sizeof(int), 1, fp); //写入最高分
    for (i = 0; i < snake_length; i++) {
        fwrite(&snake[i], sizeof(Point), 1, fp); //写入蛇身
    }
    fclose(fp);
}

void load_game() { //读取游戏进度
    FILE *fp;
    int i;
    fp = fopen("snake.sav", "rb");
    if (fp == NULL) { //如果文件不存在，则初始化游戏
        init_map();
        init_snake();
        create_food();
        return;
    }
    fread(&snake_length, sizeof(int), 1, fp); //读取蛇的长度
    fread(&direction, sizeof(char), 1, fp); //读取蛇的方向
    fread(&score, sizeof(int), 1, fp); //读取分数
    fread(&max_score, sizeof(int), 1, fp); //读取最高分
    for (i = 0; i < snake_length; i++) {
        fread(&snake[i], sizeof(Point), 1, fp); //读取蛇身
        map[snake[i].y][snake[i].x] = 1; //更新地图
    }
    fclose(fp);
}

int main() {
    srand((unsigned)time(NULL)); //随机数种子
    load_game();
    while (1) {
        draw_map();
        move_snake();
        if (_kbhit()) { //检测按键
            char ch = _getch();
            switch (ch) {
                case 'w': case 's': case 'a': case 'd': direction = ch; break; //改变方向
                case 'q': save_game(); return 0; //退出游戏并保存进度
            }
        }
        Sleep(100); //延时
    }
}