解释代码贪吃蛇double random(double start, double end) { return start + (end - start) * rand() / (RAND_MAX + 1.0); }

这段代码是一个函数，接受两个参数start和end，返回一个在[start, end)范围内的随机浮点数。具体实现方法是使用rand()函数生成一个0到RAND_MAX之间的整数，然后将其除以RAND_MAX+1.0得到0到1之间的随机小数，再将其乘以(end-start)，最后加上start，即可得到在[start, end)范围内的随机浮点数。

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解释一下贪吃蛇的代码

贪吃蛇是一种经典的游戏，玩家通过控制一条蛇在一个有边界的区域内移动，吃掉食物来增长身体长度，同时要避免撞到自己的身体或者撞到边界。下面是一个简单的贪吃蛇代码示例：

import pygame
import random

# 初始化游戏
pygame.init()

# 定义游戏区域大小和方格大小
width, height = 640, 480
grid_size = 20

# 创建游戏窗口
window = pygame.display.set_mode((width, height))
pygame.display.set_caption("贪吃蛇")

# 定义颜色
black = (0, 0, 0)
white = (255, 255, 255)
red = (255, 0, 0)

# 定义蛇的初始位置和速度
snake_pos = [[100, 50], [90, 50], [80, 50]]
snake_speed = [grid_size, 0]

# 定义食物的初始位置
food_pos = [random.randrange(1, width // grid_size) * grid_size,
            random.randrange(1, height // grid_size) * grid_size]
food_spawned = True

# 游戏主循环
running = True
while running:
    # 处理事件
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False

    # 控制蛇的移动
    snake_pos[0][0] += snake_speed[0]
    snake_pos[0][1] += snake_speed[1]

    # 判断蛇是否吃到食物
    if snake_pos[0] == food_pos:
        food_spawned = False
        snake_pos.append([0, 0])

    # 绘制游戏区域
    window.fill(black)
    for pos in snake_pos:
        pygame.draw.rect(window, white, pygame.Rect(pos[0], pos[1], grid_size, grid_size))
    pygame.draw.rect(window, red, pygame.Rect(food_pos[0], food_pos[1], grid_size, grid_size))

    # 更新窗口显示
    pygame.display.flip()

# 退出游戏
pygame.quit()

这段代码使用了pygame库来实现贪吃蛇游戏的基本功能。其中，通过控制蛇的位置和速度来实现蛇的移动，判断蛇是否吃到食物并增长身体长度，绘制游戏区域和蛇的身体以及食物等。

双人贪吃蛇java 代码_java 双人贪吃蛇

以下是一个简单的Java双人贪吃蛇游戏的代码示例：

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class SnakeGame extends JFrame {

    private final int B_WIDTH = 300;
    private final int B_HEIGHT = 300;
    private final int DOT_SIZE = 10;
    private final int ALL_DOTS = 900;
    private final int RAND_POS = 29;
    private int DELAY = 140;

    private final int x[] = new int[ALL_DOTS];
    private final int y[] = new int[ALL_DOTS];

    private int dots;
    private int apple_x;
    private int apple_y;

    private boolean leftDirection = false;
    private boolean rightDirection = true;
    private boolean upDirection = false;
    private boolean downDirection = false;
    private boolean inGame = true;

    private Timer timer;
    private Image ball;
    private Image apple;
    private Image head;

    private int player1Score = 0;
    private int player2Score = 0;
    private boolean player1Turn = true;

    public SnakeGame() {

        initGame();
    }

    private void initGame() {

        addKeyListener(new TAdapter());

        setBackground(Color.black);
        setFocusable(true);

        setPreferredSize(new Dimension(B_WIDTH, B_HEIGHT));
        loadImages();
        initGameBoard();

    }

    private void loadImages() {

        ImageIcon iid = new ImageIcon("dot.png");
        ball = iid.getImage();

        ImageIcon iia = new ImageIcon("apple.png");
        apple = iia.getImage();

        ImageIcon iih = new ImageIcon("head.png");
        head = iih.getImage();
    }

    private void initGameBoard() {

        dots = 3;

        for (int z = 0; z < dots; z++) {
            x[z] = 50 - z * 10;
            y[z] = 50;
        }

        locateApple();

        timer = new Timer(DELAY, new GameCycle());
        timer.start();
    }

    @Override
    public void paintComponent(Graphics g) {
        super.paintComponent(g);

        doDrawing(g);
    }

    private void doDrawing(Graphics g) {

        if (inGame) {

            g.drawImage(apple, apple_x, apple_y, this);

            for (int z = 0; z < dots; z++) {
                if (z == 0) {
                    g.drawImage(head, x[z], y[z], this);
                } else {
                    g.drawImage(ball, x[z], y[z], this);
                }
            }

            Toolkit.getDefaultToolkit().sync();

        } else {

            gameOver(g);
        }
    }

    private void gameOver(Graphics g) {

        String msg = "Game Over!";
        String msg2 = "Player 1 Score: " + player1Score + " Player 2 Score: " + player2Score;
        Font small = new Font("Helvetica", Font.BOLD, 14);
        FontMetrics metr = getFontMetrics(small);

        g.setColor(Color.white);
        g.setFont(small);
        g.drawString(msg, (B_WIDTH - metr.stringWidth(msg)) / 2, B_HEIGHT / 2);
        g.drawString(msg2, (B_WIDTH - metr.stringWidth(msg2)) / 2, (B_HEIGHT / 2) + 20);
    }

    private void checkApple() {

        if ((x[0] == apple_x) && (y[0] == apple_y)) {

            dots++;
            locateApple();
            if (player1Turn) {
                player1Score++;
            } else {
                player2Score++;
            }
        }
    }

    private void move() {

        for (int z = dots; z > 0; z--) {
            x[z] = x[(z - 1)];
            y[z] = y[(z - 1)];
        }

        if (leftDirection) {
            x[0] -= DOT_SIZE;
        }

        if (rightDirection) {
            x[0] += DOT_SIZE;
        }

        if (upDirection) {
            y[0] -= DOT_SIZE;
        }

        if (downDirection) {
            y[0] += DOT_SIZE;
        }
    }

    private void checkCollision() {

        for (int z = dots; z > 0; z--) {

            if ((z > 4) && (x[0] == x[z]) && (y[0] == y[z])) {
                inGame = false;
            }
        }

        if (y[0] >= B_HEIGHT) {
            inGame = false;
        }

        if (y[0] < 0) {
            inGame = false;
        }

        if (x[0] >= B_WIDTH) {
            inGame = false;
        }

        if (x[0] < 0) {
            inGame = false;
        }

        if(!inGame) {
            timer.stop();
        }
    }

    private void locateApple() {

        int r = (int) (Math.random() * RAND_POS);
        apple_x = ((r * DOT_SIZE));

        r = (int) (Math.random() * RAND_POS);
        apple_y = ((r * DOT_SIZE));
    }

    private class TAdapter extends KeyAdapter {

        @Override
        public void keyPressed(KeyEvent e) {

            int key = e.getKeyCode();

            if (key == KeyEvent.VK_LEFT && !rightDirection) {
                leftDirection = true;
                upDirection = false;
                downDirection = false;
            }

            if (key == KeyEvent.VK_RIGHT && !leftDirection) {
                rightDirection = true;
                upDirection = false;
                downDirection = false;
            }

            if (key == KeyEvent.VK_UP && !downDirection) {
                upDirection = true;
                rightDirection = false;
                leftDirection = false;
            }

            if (key == KeyEvent.VK_DOWN && !upDirection) {
                downDirection = true;
                rightDirection = false;
                leftDirection = false;
            }
        }
    }

    private class GameCycle implements ActionListener {

        @Override
        public void actionPerformed(ActionEvent e) {

            if (inGame) {

                checkApple();
                checkCollision();
                move();

                if (player1Turn) {
                    player1Turn = false;
                } else {
                    player1Turn = true;
                }

            }

            repaint();
        }
    }

    public static void main(String[] args) {

        EventQueue.invokeLater(() -> {

            JFrame ex = new SnakeGame();
            ex.setVisible(true);
        });
    }
}

这个示例代码使用了Java Swing库来创建游戏窗口和图形界面，同时实现了基本的游戏逻辑和双人模式。你可以根据自己的需求对代码进行修改和扩展。