验证码

package yanzhenma;

import java.util.Random;
import java.util.Scanner;

public class CaptchaGenerator {
    public static void main(String[] args) {
        // 生成随机验证码
        String captcha = generateCaptcha();
        System.out.println("生成的验证码为：" + captcha);

        // 接收用户输入
        Scanner scanner = new Scanner(System.in);
        System.out.print("请输入验证码：");
        String userInput = scanner.nextLine();

        // 验证用户输入的验证码
        boolean isValid = validateCaptcha(captcha, userInput);
        if (isValid) {
            System.out.println("验证码输入正确！");
        } else {
            System.out.println("验证码输入错误！");
        }
    }

    // 生成随机验证码
    private static String generateCaptcha() {
        String chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
        StringBuilder sb = new StringBuilder();
        Random random = new Random();

        for (int i = 0; i < 6; i++) {
            int index = random.nextInt(chars.length());
            sb.append(chars.charAt(index));
        }

        return sb.toString();
    }

    // 验证验证码
    private static boolean validateCaptcha(String generatedCaptcha, String userInput) {
        return generatedCaptcha.equals(userInput);
    }
}