2、模拟一个银行存款的程序。假设有三个储户都去银行往同一个账户进行存款，一次存100，每人存三次。要求储户每存一次钱，账户余额增加100，并在控制台输出当前账户的余额。

package com;

class Bank {
    private int money=0;
    public void deposits(){
        money+=100;
    }
    public String toString() {
        return "\t余额："+money+"元";
    }

    public int getMoney() {
        return money;
    }
    public void setMoney(int money) {
        this.money = money;
    }
}
class user implements Runnable {
    Bank bank = new Bank();
    public void run(){
        int num = 0;
        while(num <3){
            num++;
            synchronized(this){
                bank.deposits();
                System.out.println( Thread.currentThread().getName()
                        +      "正在"+(num)+"次存100元"+ bank.toString());
            }
        }
    }
}

public class Test {
    public static void main(String[] args) {
        user user = new user();
        new Thread(user,"用户A").start();
        new Thread(user,"用户B").start();
        new Thread(user,"用户C").start();
    }
}