snake.c

/*
descript:snake game use cursor
author:claude-4.5-haiku
use:10min
*/
// ==== 修正版：减少闪烁，for循环变量提前，速度300ms，蛇为*，果实为$，修复bug，高亮所有修改 ====

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

#define WIDTH 40
#define HEIGHT 20
#define MAX_TAIL 200

enum Direction { STOP = 0, LEFT, RIGHT, UP, DOWN };
int x, y, fruitX, fruitY, score;
int tailX[MAX_TAIL], tailY[MAX_TAIL];
int nTail;
enum Direction dir;
int gameOver = 0;

// ==== 高亮: 使用缓冲区绘图减少闪烁 ====
char screen[HEIGHT + 2][WIDTH + 3]; // 屏幕缓冲行,每行多两用于边界

void generateFruit() {
    int valid = 0;
    int i;
    while (!valid) {
        fruitX = rand() % WIDTH;
        fruitY = rand() % HEIGHT;
        valid = 1;
        if (fruitX == x && fruitY == y) {
            valid = 0;
            continue;
        }
        for (i = 0; i < nTail; i++) {
            if (tailX[i] == fruitX && tailY[i] == fruitY) {
                valid = 0;
                break;
            }
        }
    }
}

void setup() {
    dir = RIGHT; // ==== 高亮: 修正，初始使蛇自动向右移动 ====
    x = WIDTH / 2;
    y = HEIGHT / 2;
    srand((unsigned int)time(NULL));
    generateFruit();
    score = 0;
    nTail = 0;
    gameOver = 0;
}

void draw() {
    int i, j, k;
    // ==== 高亮: 使用缓冲区代替system("cls")，减少闪烁 ====
    for (i = 0; i < HEIGHT + 2; i++) {
        for (j = 0; j < WIDTH + 2; j++) {
            screen[i][j] = ' ';
        }
        screen[i][WIDTH + 2 - 1] = 0; // 结尾
    }

    for (j = 0; j < WIDTH + 2; j++) {
        screen[0][j] = '#';
        screen[HEIGHT + 1][j] = '#';
    }
    for (i = 1; i <= HEIGHT; i++) {
        screen[i][0] = '#';
        screen[i][WIDTH + 1] = '#';
    }
    // ==== 高亮: 使用$显示果实 ====
    screen[fruitY + 1][fruitX + 1] = '$';
    // ==== 高亮: 用*显示蛇头 ====
    screen[y + 1][x + 1] = '*';
    // ==== 高亮: 用*显示蛇身 ====
    for (k = 0; k < nTail; k++) {
        screen[tailY[k] + 1][tailX[k] + 1] = '*';
    }

    // ==== 高亮: 直接设置光标到左上,减少闪烁 ====
    COORD coord = { 0, 0 };
    HANDLE hOut = GetStdHandle(STD_OUTPUT_HANDLE);
    SetConsoleCursorPosition(hOut, coord);

    for (i = 0; i < HEIGHT + 2; i++) {
        printf("%s\n", screen[i]);
    }
    printf("分数: %d\n", score);
}

void input() {
    // ==== 高亮: 修复鼠标点击或方向键导致卡死问题，过滤特殊键 ====
    if (_kbhit()) {
        int ch = _getch();
        if (ch == 224 || ch == 0) {
            _getch(); // 忽略扩展码
            return;
        }
        switch (ch) {
        case 'a':
        case 'A':
            if (dir != RIGHT) dir = LEFT;
            break;
        case 'd':
        case 'D':
            if (dir != LEFT) dir = RIGHT;
            break;
        case 'w':
        case 'W':
            if (dir != DOWN) dir = UP;
            break;
        case 's':
        case 'S':
            if (dir != UP) dir = DOWN;
            break;
        case 'x':
        case 'X':
            gameOver = 1;
            break;
        }
    }
}

void logic() {
    int i;
    // for (int i = nTail - 1; i > 0; i--) {
    for (i = nTail - 1; i > 0; i--) { // ==== 高亮: 变量提前，支持旧标准 ====
        tailX[i] = tailX[i - 1];
        tailY[i] = tailY[i - 1];
    }
    if (nTail > 0) {
        tailX[0] = x;
        tailY[0] = y;
    }
    switch (dir) {
    case LEFT:
        x--;
        break;
    case RIGHT:
        x++;
        break;
    case UP:
        y--;
        break;
    case DOWN:
        y++;
        break;
    default:
        break;
    }
    if (x < 0 || x >= WIDTH || y < 0 || y >= HEIGHT) {
        printf("游戏结束! 最终得分: %d\n", score);
        gameOver = 1;
        return;
    }
    for (i = 0; i < nTail; i++) {
        if (tailX[i] == x && tailY[i] == y) {
            printf("游戏结束! 最终得分: %d\n", score);
            gameOver = 1;
            return;
        }
    }
    if (x == fruitX && y == fruitY) {
        score += 10;
        if (nTail < MAX_TAIL) nTail++;
        generateFruit();
    }
}

int main() {
    int stepMillis = 300; // ==== 高亮: 速度300ms ====
    // ==== 高亮: 隐藏光标 ====
    CONSOLE_CURSOR_INFO cursorInfo;
    HANDLE hOut = GetStdHandle(STD_OUTPUT_HANDLE);
    GetConsoleCursorInfo(hOut, &cursorInfo);
    cursorInfo.bVisible = FALSE;
    SetConsoleCursorInfo(hOut, &cursorInfo);

    setup();
    COORD coord = { 0, 0 };
    SetConsoleCursorPosition(hOut, coord);

    while (!gameOver) {
        draw();
        input();
        logic();
        Sleep(stepMillis);
    }
    // ==== 高亮: 恢复光标可见 ====
    cursorInfo.bVisible = TRUE;
    SetConsoleCursorInfo(hOut, &cursorInfo);

    printf("按任意键退出...\n");
    _getch();
    return 0;
}