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スポーツコート（テニス、バドミントン、バスケットボール）検索がもっと簡単に！

PlayGoは、日本のスポーツ愛好者に最適なアプリです！周辺の空きスポーツコートを自動で検索し、リアルタイムで通知します。練習の計画や試合の準備に、PlayGoがあなたの時間を節約します。

主な機能：

自動コート検索機能: 空きスポーツコートを自動で検索できます。

通知機能: コートが空いたらリアルタイムにお知らせします。

カスタム設定: コートの場所、時間帯、その他の条件をフィルターで設定可能。

使いやすいデザイン: シンプルで直感的な操作感。

日本語＆英語対応: 言語を簡単に切り替え可能。

PlayGoは初心者からプロまで、すべてのスポーツプレイヤーにぴったりです。計画的に練習をしたい方も、直前にコートを見つけたい方も、PlayGoがサポートします！

今すぐPlayGoをダウンロード！

スポーツコート探しの手間を省き、大好きなスポーツに集中しましょう。次の試合があなたを待っています！

[アプリ内課金]

アプリはユーザーに、利用可能なコートが見つかった場合に通知します。通常のユーザーには、限定された回数の無料通知が提供されます。通知回数の上限に達すると、それ以上の通知は提供されません。一部のコートの通知はVIP専用です。

月額VIPプラン:

ユーザーは自動更新サブスクリプション（月額1000円）に加入してVIP会員になることで、制限を解除できます。VIP会員は、希望するコートが利用可能になるたびに、総回数の制限なく通知を受け取ることができます（ただし、1日の通知回数に制限が設けられる可能性があります）。

VIPユーザーには広告が表示されません。

通知追加オプション:

1回の通知を200円で購入、または3回の通知を500円で購入できます。

プライバシーポリシー(Privacy Policy)：https://kaili.ai/playgo-privacy-policy

利用規約(Terms of Use)：https://www.apple.com/legal/internet-services/itunes/dev/stdeula

playgo.official.contact@gmail.com.

Privacy Policy

1. Introduction

Welcome to PlayGo! Your privacy is important to us. This Privacy Policy explains how we collect, use, and protect your information when you use our app.

2. Information We Collect

We collect your contact and sports court preference data to help you find available courts. This data is used only for this purpose and is not stored or shared with third parties.

3. How We Use Your Information

We use your contact and sports court preference data to notify you with preferred courts in real time.

4. Sharing Your Information

We do not sell or rent your personal information to third parties. Data may be shared with service providers only to provide core app features, such as apple push notification service.

5. Data Security

We implement security measures to protect your data. However, no method of transmission over the Internet is 100% secure.

6. User Rights

You can perform data deletion in the app.

7. Contact Information

If you have questions about this Privacy Policy, contact us at: playgo.official.contact@gmail.com.

8. Updates to the Privacy Policy

We may update this Privacy Policy from time to time. Updates will be posted on this page with the effective date.

至于是什么创伤，具体不谈了，简而言之一句话：所有的努力不仅都喂了狗，还被狗狠狠咬了好几口（突然上线的求生欲：如有雷同，纯属巧合）。

那时候因为这些创伤，心灰意冷，略感绝望，迫切想要换个新的工作环境，也做了一些努力，最后幸运地成功了（此处感谢新环境的收留之恩）。

然而，我直到最近才突然意识到，虽然环境改变了，自己那时候也以为过去的一切将不会再影响我，但其实，创伤带来的负面影响还在持续，但是我一直以来都没有意识到这一点。现在突然醒悟之后，做出的总结如下：仿佛就是自我的内核产生了破碎，直至最近才修补完毕，也是等到修补完毕之后，才突然意识到曾经有破碎过这件事情。当然，就算修补完成了，裂缝还是会存在。希望我能够从过去的经验教训中有所成长，将来能够更好地处理这种事情吧。

至于破碎的具体表现之一，就是在工作中倾向于使用防御模式，因此容易起冲突。那时候刚到新环境之后，因为前后两个环境的工作风格相差较大，因此沿袭着旧环境风格的我，和新环境的成员有一些冲突。虽然我那时候想的是：都是些小冲突，每个人的立场和想法确实可以有很大不同，偶尔也是厌蠢症与性格中急躁的部分在作祟。但是现在想来，这其中的主要原因，就是创伤在作祟，让我的情绪波动比平常更大，也更加容易陷入不恰当的处理方式和态度。不过说实话那时候完全没有想到是这一层原因，只是最近突然醒悟，这才意识到了这更为深层的原因。

幸运的是生活中几乎没什么影响，主要感恩于身边有内核极其稳定、心灵极其纯真善良的家人。

有人问我：那么如果下次再遇到这种事情，你会如何处理？我现在的回答：就让本该发生的事件发生吧。在工作中需要拎得清，不能有过多不属于当前职位的责任感，在期待的范围内好好干活就好了（手动狗头）。

有个聪明人曾经说了一句很有道理的话：let people learn from their mistakes.

Considering the product requirements, the website should offer an opportunity for purchasers to opt in. Once purchasers choose to enable the new automation feature, the website can begin sending greeting messages to newly bookmarked suppliers. To prevent accidental clicks and messages, there is a 10-minute waiting period after the purchaser bookmarks the supplier before the message is sent. In order to facilitate analysis of the new feature, the data scientist also desires to obtain the timestamp indicating when the greeting messages were sent.

The website employs a micro-service architecture and already incorporates services such as the purchaser service, which utilizes a database to store purchaser-related data, the supplier service, which uses a database to store supplier-related data, and the messaging service for sending messages. Suppose you are the software engineer tasked with implementing this feature, how do you plan to design it?

It's quite straightforward to store the purchaser opt-in data in the purchaser-related database through the purchaser service and store the timestamp through the supplier service follow a similar approach. When it comes to sending greeting messages with a 10-minute delay after purchasers bookmark certain suppliers, there are multiple options to consider.

One commonly used approach is to create an API that handles the scheduling and sending of messages. This API is called immediately after the bookmark action occurs. If the bookmark action is initiated by a button, the API call is triggered behind the scene when the button is clicked.

Another solution is to produce and publish events for the bookmark action. These events include important data such as the purchaser ID, supplier ID, bookmark action (bookmark or rescind), and other relevant information. By doing this, multiple consumers can subscribe to, consume, and process the same event, each dealing with different logic. This approach enhances scalability and flexibility.

An important aspect of the design is determining how to schedule a 10-minute delay before sending out the message. Common approaches, such as Kafka and RabbitMQ, can accomplish this, but they require manual efforts to set up the schema and pipeline. Alternatively, workflow tools like Temporal and Cadence simplify and expedite the entire implementation.

The final design, utilizing the event consumer approach, with the Temporal workflow tool, is as follows:

Before the transition, working as a machine learning engineer in my previous company is generally a memorable experience. I graduated from the ideal university way of doing deep learning (with ample resources of data and computation), and found that doing machine learning in an industrial company without enough data is really disappointing. The bad loop is that no data -> no machine learning scenarios -> no meaningful work -> no skills improvement -> no idea of improvement -> no data ... That's why I spent time on one and another one PoCs and finally proved some of them are promising. But knowing them promising is usually the final step of the work, and the team moved on to another totally different work. Very few times some work can be applied to improve the online system, but finally you will find it's nothing related to modeling or even machine learning.

Not all industrial companies are like this. Staying in my previous company is not a bad thing, considering the cost-effectiveness of working hours and wages. Just because I really wanted to learn/do something really meaningful and impactful, I chose to seek new opportunities.

Then I found the chance to work in my current company as a full stack software engineer.

So far I am feeling pretty fulfilled. The current work is pretty interesting. I have learnt much knowledge about frontend, API design, backend, and microservices. The current company has a powerful platform and its own technical stacks, so I also have taken great advantage of it. Senior engineers in the team are intelligent and reliable. The product manager is also full of wisdom and great ideas of products. The manager also provides much help on career growth and technical discussions. No matter working alone on a specific feature, or cooperating with other team members, everything is relaxing and enjoyable.

After being more and more familiar with the team's products and technical stacks, one important thing for me is to keep learning new knowledge on company-wide techniques and information.

Being insensitive is always the first step to stopping growth.

Recently I feel like it is time to look for another mansion to live in Tokyo.

Time flies, I have been living in my current mansion in Asakusa for nearly 2 years. The room is small (25 ㎡) but has all the spaces needed for daily life.

And I have been working from home for nearly one and a half years. Sometimes I think that my bedroom is too small and I cannot do any activities because I put a double-sized bed in it. My kitchen is not big enough, I don't have enough space to handle food and cannot knead the dough for baking.

Several times I wanted to move to another ideal room, but it seemed too cumbersome to put my ideas into action (Yeah I am lazy), so I have been living in the same room until now.

My contract will expire in this September, so now it is the right time to think about what I really want for housing.

After some considerations, I found that for me, there are a few points that I do care about:

1. A beautiful view from the balcony.
   Working from home can really reshape people's habits. Now I almost spend all my weekdays at home and go shopping two or three times a week. The only way to make me feel that I am not isolated from the outside world is to have a look from my balcony. In the daytime, I would like to open the curtains to let sunlight enter my room. It really helps me relax and keep a good sense in the global pandemic. At present, I can almost see the entire Tokyo Skytree from my balcony, and I think that is kind of my spiritual belief now.

2. A runway nearby.
   I no longer go to the gym to practice, but I do need to keep my running practice. So I think it is necessary to have a runway near my home. For safety and pollution reasons, running on the street is not my choice. I find that running along the river is a good choice. And currently, I mainly run along the Sumida River, enjoying the beautiful scenery while running.

3. The house should be as new as possible.
   No more explanation for this one.

4. Near supermarkets.
   There are no shared bicycles in Tokyo. It's not convenient if supermarkets are far away.

5. A large kitchen?
   Maybe this one can be considered later. Baking does not happen very often. A basic kitchen can handle cooking for one person's meals.

I think my current room suits me well. It satisfies all the above conditions except for a large kitchen. I would like to continue to live here if possible, but also look forward to living in a new environment and experiencing more. So I still need to think about housing for a while. After all, no one knows what will happen tomorrow.

自从2019年9月份从上海飞去日本东京开始工作后，我已经一年多没有回过家了。本来美滋滋打算每年可以搭乘“千元机”从东京直飞宁波回家起码一次吧，到后面我发现“千元机”都变成“万元机”了还不一定有票。在犹犹豫豫、拖拖延延中，我终于在今年10月份买好了回国的机票，并顺利在12月13号从东京起飞回到了深圳。

“五个一”航空政策实施以来，从日本回国的机票一开始是完全买不到。后来终于有票了，但贵的离谱，最高能达到5万人民币。再后来，我看着机票价格一路降到了3万、1万、1万以下，在预估好时间和钱包承受能力后，最终买了深圳航空从东京飞往深圳的机票，打算在深圳隔离结束后再从深圳飞回宁波。

回国之前，需要在登机前两日内去驻日大使馆指定的机构进行新冠的核酸检测和血清检测，只有获得这两个检测的双阴性证明，才能被允许登上飞机。（所以万一在检测后发现自己被感染了，就回不到祖国爸爸的怀抱了TT。）日本的检测真的有点水，核酸检测是取了口水，血清检测是在一个试剂上滴了一滴血，然后就让我回家等通知了。我早上10点去做了检测，当天就拿到了双阴性证明书。接下来就在微信小程序上传证明书换取国际健康码，等码绿了就可以凭着此码登机了。

起飞那天，我早早去了机场，但已经有人在排队了。托运好行李后，又在手机上填了一个什么表，生成了一个码，截个图，需要在入境的时候使用。之后过安检，和果佬一起在里面逛逛街、买买酒，登上飞机开始起飞。在上飞机的廊道里我还看到了高清无码的我海：

飞了5个多小时。我在飞机上看了一部《霍元甲》和一部《找到你》，终于到达了深圳。

刚下飞机，我们就来到一个大厅按号入座，依次前往各个地点办理手续。第一个地点检查了护照、扫了码；第二个地点进行了流调（流行病学调查）；第三个地点好像被一个工作人员在护照上贴了个没什么用的“温馨提示”的贴纸；第四个地点终于做了新冠检测：喉咙+鼻子，不得不说跟日本相比，国内检测真的严格，做完鼻腔检测后我感觉我的鼻子都通透了；第五个地点在一堆行李中找出自己的行李；第六个地点坐上了唯一停在那的一辆大巴，载着我们开往了之后要进行隔离的酒店。在机场总共可能用时1个小时左右。

我在大巴上一路看着百度地图，一路猜着去哪家神仙酒店呢？结果大巴开到了一家不能点外卖，每人只能收一次快递的酒店。我一开始被分配到的房间的空调坏了，赶紧跑去前台换了一间房，结果洗完澡后又发现这间房的吹风机坏了。。。又赶紧让前台送来了新的吹风机。 一切就绪后，在凌晨2点左右开始睡觉，然后不知为何失眠到了4、5点。可能太兴奋与紧张了吧，后面几天睡得就很好了。入住当晚是唯一相对自由的时间段，我下一次再从房间出来就是解除隔离之后了。

第二天起床后，我用美团外卖买了瑜伽垫，虽然最终也没用到几次，但是无聊的时候可以玩玩健身环游戏，保持下良好心情。

每天早晚，会有医护人员过来量体温，并问有没有哪里不舒服。入住的第6天和第13天，我们分别做了一次核酸检测。只有当全机组人员都是阴性，我们才能在14天后结束隔离，否则，隔离会被延长。所幸，我乘坐的飞机全员检测阴性。

两礼拜的时间，主要在远程工作中度过。酒店的wifi有问题，还好果佬给我带了网线，大部分时间用有线工作基本没有问题。我们是27号晚上解除隔离，我额外又住了一晚，28号早上从酒店出发去深圳宝安机场，搭下午的飞机飞回宁波。

从机场出发到家后，我又要开始在家的7天居家隔离，以及在第7天和第14天分别再去做一次检测。所以预计真正自由的时候是2021年1月4日，那时又要开始新的一年的打工了。

现在，我已经在国内待了近20天了。这期间完全没有担心自己会得新冠也没有关心与此相关的霓虹新闻。只能说，香，真香（手动狗头）。

Ever since I sold myself to society in 2018, I embarked on the road for working with no turn-back.

I chose Mercari as the first company to start a full-time job. The flight to Tokyo was in late September 2019. And I joined Mercari on 2019.10.01 as a new grad.

Then I had to take part in a 2-month training. It's interesting, though didn't help much in terms of technology. After that, I had a skill test with other new grads and an interview to see if I could be assigned to the team according to my expectations. Fortunately, I was able to join my first wish team, the ML listing team.

Though Mercari is a pure Japanese company founded by the Japanese, it has a fairly good international culture compared to some famous American companies ( such as Google, Facebook, etc.). There are pretty many foreign engineers in the company, and English is one of our official languages. In my team, there are no Japanese engineers. My manager is from France and my tech leader is from America. So I only communicate with them in English, which is why my Japanese is still not good enough.

Before Covid-19, we had a fixed core time work style. On every workday, employees must be in the office between 12 pm to 4 pm. And we could decide when to start work and when to end work, as long as we could ensure to work for 8 hours each workday. Due to the Covid-19 outbreak, Mercari asked us to work from home since this February, and I have been working from my small home in Tokyo for nearly 1 year. Later, Mercari revised the work style rules. We have shifted from a fixed core time work style to a more flexible free work style. As long as we can ensure 8 hours of work each workday, we can do our work at any time. Of course, we also need to make sure that meetings are held as usual.

During the past 1 year, I have been more of a data analyst than a model magician. Here in Mercari, we have many tasks to complete, but in the meantime, due to the lack of useful training data, many of these tasks cannot be performed now. One of my responsibilities here is to think about how to improve the situation and make real ML/DL practices possible. And I believe that as I spend more time on my career in Mercari, I can gradually come up with real ML solutions for our business.

今天是2020年11月5日，没什么特殊意义。纯粹是因为突然想起了这个荒废已久的博客，意外顺利地登录进来后，想要提笔写点东西。写点什么呢，那就随便谈一谈今年发生的事情吧。

今年到此为止唯一值得被载入史册的事件自然是新冠病毒席卷全球了。我本来打算2月份左右回国一趟，后来因为新冠在武汉爆发进而在全中国爆发，所以暂时打消了回国的念头。后来我司决定让员工们在家远程上班，所以我就从2月份开始一直在家上班，直到最近9月份才去公司办了点杂事。

在家办公期间，有段心理上十分艰难的时光。孤独、恐惧、甚至抑郁，这些负面因素能够随时把我淹没。那段时间的睡眠质量也非常差，经常躺在床上连续2个小时睡不着觉。有时就算身体比较累，但是精神依然很活跃，虽然现在已经忘记了当时在想什么，估计是在为未知的危险明天而提心吊胆吧。那时也经常感到呼吸不顺，但是血氧计测出来是正常水平，想必是心理压力过大了。

因此大概在4、5月份的时候，我在想要不直接回国得了，起码有亲人和朋友们陪伴。但是因为防火墙，回国可能无法顺利办公，所以一直在犹犹豫豫间拖延着。再加上五个一政策，基本买不到机票，所以一直在日本待到现在。

现在回想，那段人生到此为止最艰难的时光我都一个人挺过来了，大概以后是能够一个人扛下同等的孤独了。可能现在的心态也离坦然面对孤独终老不远了吧。

期间约了几个公司同事和朋友偶尔聊聊天。两个日本小姐姐，一个人特别好，当我在twitter散发负能量的时候来安慰我，主动跟我约会议聊天，尽管我们语言并不十分相通，后来我也主动去约了她几次。另一个是我主动去找她，也聊了几次。再后来我拉了几个中国的同事搞了个每周四晚上的聊天会议，其间互相调侃、讨论，也十分温馨。

再后来，逐渐对特殊状态麻木了，想要出去旅行玩耍了。约了几个朋友，去了日本不少城市，从夏天体验到秋天。去高尾山爬山，从春天到夏天，最近的秋天倒还没怎么去过。和浪姐姐去镰仓、伊豆、八丈岛、仙台等地，去冲浪、玩水、泡温泉、看风景。搭老卢的车去兜风、散心。当然，我在9月份搞了个9连休，用其中7天一个人去名古屋、金泽、善光寺、松本、轻井泽逛了逛。但是，这次旅行后，我发现一个人旅游确实没什么意思，旅途中的风景与活动基本大同小异。旅行最开心的应该是与同行人一起分享喜悦与惊喜，在闲暇中获得不一样的人生体验与美好回忆。

最后讲点与以上内容没什么相关的话，这也是我最近的一个感悟：最好的感情状态，对我而言是，在一见钟情的基础上持续日久生情，无论是友情，还是其它。

Today I want to talk about social applications.

The biggest problem I face with social softwares available in Tokyo is that I have too many options, and none of them can meet my all needs. In other words, I have to use multiple softwares at the same time. Some of my friends mainly use APP 1, some mainly use APP 2, some mainly use APP 3, and so on.

Here are some social softwares I have used in Tokyo so far:

1. Line: Similar to WeChat. It is mainly used for direct communication with others I think. Line Pay is built in, and I can use it to pay stores and friends(like WeChat Pay and Alipay). Also, you can make a post there and your friends can view and comment(like the Moments function built in WeChat). One drawback I found was the limited number of stores that support Line Pay, so I can't use it all the time.

2. Twitter: It is mainly used for posting with a word limit. All users in Twitter can view and comment on your posts, they can also retweet your posts. Also, you can send direct messages to others. No payment function. I like to use it to post my daily thoughts.

3. Facebook: Mainly similar to the Moments function built in WeChat. If you want to communicate with others directly, Facebook will automatically redirect to another software called Messenger.

4. Messenger: Facebook-related communication tool.

5. Instagram: Like weaker Twitter.

6. Whatsapp: Mainly for communication.

For some reasons, all the 6 softwares I mentioned above cannot be used in China. And instead, we have WeChat, the most perfect social application, that can meet all my needs.

When I was in China, after I got a new mobile phone, the first application I would download must be WeChat. Because I mainly use it to contact with my family and friends, by text, voice and video. Also, I use WeChat Pay to process most currency transactions, not only for online shopping, but also in most stores in Hangzhou, and even hospitals. I can also use WeChat to rent a shared bike as well as to call a taxi. My ID information can be tied to my WeChat account, so I can use it to access many public resources, such as online registration for hospitals.

WeChat is also a good platform to see posts of my friends there. One good thing is, if someone is not my WeChat friend, the person cannot see my posts. I think it does protect my privacy.

Last but not least, as a lazy person, I prefer a complete software to many incomplete ones.

So this time, I have been in Tokyo for two and a half months, and I think I am used to life here.

I remember the first few days in Tokyo this time when I arrived at my empty apartment, laid out bedding on the floor, and laid down to sleep. Then I needed to buy various machines such as refrigerator, washing machine, kettle, etc. I also needed to buy my bed, mattress and other bedding. The first item I bought was curtains, since my house has a floor-to-ceiling window, and I need curtains to protect privacy. There is a very good view from my balcony, and I can clearly see the Tokyo Skytree, and you can never imagine how beautiful and colorful the tower is at night. Then I went to Bic Camera to buy various electronic machines and went to Nitori to buy various furnitures. Gradually, my empty room became a little crowded and became my first home abroad.

The first thing that is very different from Hangzhou is that delivery speed in Tokyo is too slow! It took me about 2 weeks to receive the delivery from Bic Camera and Nitori. As I lived in Hangzhou for 7 years, I can never imagine that I would spend so many days waiting for delivery. Because in Hangzhou, almost all items can be purchased online, and the goods can usually be received in about 3 days. I think one reason is that now I can only receive the goods on weekends, and the other reason is that human resources here are so scarce that they can’t arrange the shipment immediately.

When the delivery man arrives in my apartment building, he will first press the lobby button to call me through the intercom in my room, and he rarely calls me over the phone. This means I have to stay home and wait for delivery! When I have to wait at home, I feel like a prisoner in jail. I don’t like feeling not free. And I hope someday they can notify me by phone, then even if I am in my friend’s house nearby, I can still get my goods in time.

Another different thing is there are some deliveries that the postman must give me in person. Even if there is a delivery box for my room, the postman will not put these items there. Instead, he will leave a note for me and let me reschedule the time for delivery, and I should wait in my home... But in Hangzhou, even some very important documents, such as passports, the postman can place them in somewhere like delivery box and I can go there to fetch them at anytime. For things like this, I think the Japanese way is much safer.

To be continued.

So many months no updating my blog, I think it is the time to write something new.

My life has changed a lot since I started to work in another country and met many new friends. But I know I have always been the same.

I will keep this website updated as a proof of my life.

It is not easy to start a marathon, like running 10KM or even 21.0975KM. To ensure safety, runners should develop training plans and gradually achieve their goals.

As someone who had completed several 10KM small marathons before, I decided to start preparing for my first half marathon. Three months ago, with the help of Nike Run Club app, I developed a two-month training program and finally achieved my goal on July 27, 2019.

Here, I want to share my way to complete a first half marathon. Let me first introduce you to your first 10K run, assuming you are a beginner.

Based on my experience, I suggest you go from 3KM, 5KM, 7KM to 10KM. For many people who rarely run, running a lasting 3KM can be difficult. But 3KM is your first obstacle to starting a long run, so you have to overcome it. At first, you can run very slowly, but make sure you can finish it. Then, run 3KM every few days to familiarize your body with this running intensity. I do not recommend running every day because your knees need to rest.

When you think the distance of 3K is OK, you can try 5K now. From 3K to 5K should be easy, because you have overcome the biggest difficulty in running(taking the first step). After 5KM, it is natural to complete 7KM and 10KM. When you train for longer distances, interval training for shorter distances and concentrating on improving your speed is also a good method.

So far, congratulations on completing most of the half marathons!

From 10K to 21.0975KM, my advice is to follow a professional training program. You need systematic training to complete a professional running race. This way, you can avoid injuries and extend your running life as much as possible. For me, I chose the preparation training plan in the Nike Run Club app. First, I entered my data, such as height, weight, training intensity and number of times per week, then it automatically generated a training plan for me. I have completed this plan and achieved my goal, thinking it was not hard to follow.

So, keep running, keep living. In the future, my first full marathon is waiting for me.

Around the Spring Festival this year, I finished reading two technical books, one was Inside the C++ Object Model, the other was The Pragmatic Programmer: From Journeyman to Master. To some extent, both books are exhortations from C++ experts, and I saw a lot in both books that do not use C++ to do this or that. C++ is my favorite programming language, but I must admit that it is really hard to grasp the essence of it. For me, the difficulties in learning C++ lie in two aspects: one is the various features of object-oriented languages, including inheritance and polymorphism (involving various pointer and reference operations related to Virtual), the other is ABI (Application Binary Interface) without standard definition in C++, thus each major manufacturer has its own way of implementation.

It is easy to get stuck in the design idea of one programming language if I am always in touch with this language. Later, I hope to have time to get a deeper understanding of JAVA and its memory model, and to distinguish the differences between C++ and JAVA.