public static UserInfo  addFriend(int srcJKNum,int destJKNum){
		//Ĭûֻһ
		UserInfo user1=userDB.get(srcJKNum);
		UserInfo user2=userDB.get(destJKNum);
		//ǻΪ
		user1.getTeams().get(0).addBudy(user2);
		user2.getTeams().get(0).addBudy(user1);
		saveDB();//洢ļ
		return user2;
	}