In TCP implementation, when receiving the SYN request from the client, the server needs to reply the SYN + ACK packet to the client, and the client also needs to send the confirmation packet to the server. Usually, the initial serial number of the server is calculated by the server according to certain rules or adopts random numbers. However, in SYN cookies, the initial serial number of the server is obtained by hash operation and encryption of the client IP address, client port, server IP address, server port and other security values, which is called cookie. When the server suffers from SYN attack and makes the backlog queue full, the server does not reject the new SYN request, but replies the cookie (SYN serial number of the reply packet) to the client. If it receives the ACK packet from the client, the server subtracts 1 from the ACK serial number of the client to obtain the cookie comparison value, and performs a hash operation on the above elements to see if it is equal to the cookie. If equal, complete the three-way handshake directly (Note: At this time, you don't need to check whether this connection belongs to the backlog queue).
公元1627年，崇祯17岁登基，从明熹宗的手上接过了千疮百孔的大明王朝，内有权臣由魏忠贤一手把持朝政，实质上崇祯是个傀儡皇帝，政令均自魏忠贤之手，但他并非昏庸无能之辈，采取韬光养晦，以守以攻，怀柔和麻痹魏忠贤的策略，暗自培养乾练人才。待政权根基稳固之后，步步为营，稳扎稳打，终以漂亮乾练的手法解决了客魏（客氏和魏忠贤）集团，其政治手腕之娴熟，行政调动能力之强堪与清圣祖康熙扳倒权鳌拜之手法相提并论，他勤俭自律，清心寡欲，励精图治，勤勉和贤能超过了历朝历代的帝王。但大明气数已是油尽灯枯，王朝更迭的不可违之命就这样像抓阄一样抓到了崇祯的头上，他的悲剧命运就在于他不仅无法以一身之躯来阻止社稷颠覆之势，而且历史所能给予他的时间和空间也注定他成为不了一位中兴之主。1644年，李自成率农民军攻占北京，崇祯帝自缢于煤山，明朝被推翻。李自成入京后，派降将唐通带白银5万两和吴三桂父亲吴襄的书信。前去招降吴三桂。为保全自己在北京的财产和地位。吴三桂意欲归顺闯王。后闻爱妾陈圆圆被李自成纳为妾的消息后，冲冠一怒为红
二战后期，战争越来越残酷，中尉加里森从监狱里找来一些杀人犯，骗子，强盗，小偷组成一支前所未有的敢死队。这些人各有所长且极具个性，抱着立功赎罪的目的加入到这支队伍中来。他们充分发挥各自的特长，纵横于欧洲各国，深入敌后，一次次打入敌军，营救战友，轰炸雷达站，绑架德军元帅，偷取秘密情报，盗取德军物资，摧毁敌人计划，打击黑帮团伙，把德国人骗得晕头转向，打得落花流水。这些人虽然是在押的囚犯，但却骁勇善战，有勇有谋，有情有义而且风趣诙谐，即使是最危急的时刻也不忘幽它一默。虽然他们也有缺点，常常抱怨任务艰巨，偶尔也有小偷小摸，甚至于关键时刻撒手不管，但是正是这些缺点使他们更加真实，可信，也更加可爱。由于他们的英勇表现，德军一次次地受到了沉重打击，战争形势一步步转变。
2. Credibility includes two elements: one is the credibility of the disseminator, including honesty, objectivity, fairness and other character conditions; The other is professional authority, that is, whether the disseminator has the right to speak and the qualification to speak on specific issues. Credibility is divided into two types: high credibility and low credibility, namely stars and ordinary people. For the audience, if it comes from different disseminators, people's acceptance of it is also different. The higher the reputation of the star, the higher its credibility. Choosing a star to speak for a certain brand, relying on the star's leadership charm, the enterprise can transfer the star charm to the product and transform it into the connotation of the product to endow the product with new vitality and cordial association.
1961年夏， 艾米尔·黑尔贝格刚刚从军队退役复员。 他来 到了位于巴伯斯贝格的DEFA电影公司：这是一个充斥着无尽的魔幻感和极富创造性的乐观主义的地方。在一扇巨大的拱门后面，他看到了历史悠久的被称为“梦工厂”的电影公司。他的哥哥亚亚历山大在这家公司的置景组工作， 他给艾米尔谋到了一份差事。虽然艾米尔对电影行业知之 甚少，但因为他还没有任何对未来的规划，便勉强接下了 差事。然而，当他为一部电影做群演时，他遇见了一位名 叫米露的法国舞者，一切开始发生变化......
患有男性恐惧症的宅腐女费菲与中二妖孽男海洋开始了一段“同居”生活。性格迥异的两人矛盾不断，生活变得鸡飞狗跳。而郑尔岚因为嫉妒璟顼对费菲的与众不同，开始利用职务之便不断找茬，这让费菲要出版图书成为畅销书作家的梦想不断受挫，而海洋的中二病也让他在Cosplay大赛中屡屡遇到挫折。在这最艰难的时期，原本吵闹不断的两人却成了彼此最坚实的依靠，相互鼓励走出困境。朝夕相处中，费菲渐渐发现海洋的奇怪之处，细细探究之下却发现海洋是从她的一本小说中穿越而来要给自己改写命运的炮灰男三号。
《浩九的爱情》改编自韩国网站DAUM上的同名网路漫画，讲述了从未谈过恋爱的单身男姜浩九（崔宇植饰）、游泳女神都桃姬（金宥真饰）、精英律师卞江哲（任瑟雍饰）和恋爱高手姜浩静（李秀卿饰）之间的复杂搞笑罗曼史
D > B enters the synchronized block, and since instance is not null at this time, it immediately leaves the synchronized block and returns the result to the program calling the method. E > At this point, thread B intends to use the Singleton instance, only to find that it has not been initialized, so an error occurs. Therefore, there is still the possibility of errors in the program. In fact, the running process of the program is very complicated. From this, we can see that it is more difficult and challenging to write programs especially in multi-threaded environment. We further optimized the program:
当此之时，刘邦正和众多诸侯宴饮，欢歌笑语不断。
3.15
绝望之下，他再也顾不得了，解开外衣，又除了秦淼外面的衣裳，将她紧紧搂在胸前，用自己滚烫的胸膛温暖少女冰块一样的身躯。
Then we can encapsulate a written examination method with the following code:
? Sunny day mode is used during sunny days.
此前，浙江没少被倭寇洗礼，可无论普通倭寇还是鬼倭，都是乌合之众乱战，旷日持久之下，总会被浙江深厚的底蕴所击败。
奋斗中的小镇青年遇到大城市的独居老人，同样孤独的两个人，不同的社会层次，不同的生活背景让他们之间矛盾频发、笑料百出，最终建立起跨血缘的深厚亲情。
20岁的刘奕东是个高中毕业的叛逆少女，她母亲兰姐和她继父离婚后， 搬来与她同住，两人因为她爸的死而关系紧张。26岁的张建是个木讷老 实的房产中介，业绩不好常被欺负，他并不适应北京的高压和快节奏生活，女友也离他而去。称自己23岁的秦芸娟是一名KTV陪唱女，她陪唱不陪睡，辛苦周旋在客人、同事和KTV经理之间，最大的愿望是把儿子接来身边。27岁的唐小柔没有主业，倚靠网络直播赚钱，她17岁曾拍过一本知名杂志的封面，从此认定自己是做明星的料，可是7年过去，她还只是个小透明，每天忙碌于各种试镜活动，存着一笔整容基金，做着明星梦。
照这么说的话，徐明此举是何目的？迷惑大王，让我们放松警惕？还是会计山只是个偶然，徐家的子女并不认识大王，所以发生了冲突，之后发觉为时已晚，只能被迫一条道走到黑？众人听到陈平这个分析之后，心中也多了几分怀疑，两种可能都是可能存在的。
Imitation of role models: role models can be real-life mentors or online mentors.
New ways to improve skills//175
The code drawbacks are as follows:
