直接上代码

package com.bigdat.java.day16;

import java.util.Scanner;

/*
        模拟登录,给三次机会,并提示还有几次。
 */
public class StringDemo1 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String name = "阿涛";
        String pwd ="123456";
        int num = 3;
        while (num > 0){
            num -=1;
            System.out.println("请输入账号(姓名)：");
            String n = sc.nextLine();
            System.out.println("请输入密码：");
            String p = sc.nextLine();
            if(name.equals(n) && pwd.equals(p)){
                System.out.println("身份验证成功！正在登录...");
                break;
            }else{
                System.out.println("身份验证失败，您还有"+num+"次机会！");
            }

        }
    }
}