4 Easily implement revocation and redo of requests
Public int calculation (String exp) {
城市小滑头仁杰，他假扮“三德和尚”以锄恶霸王高峰（王龙威饰）气焰，反被识破而遭痛殴。仁杰遂上少林寺要求三德和尚授其功夫，但屡试不果。最后三德允其留在寺中负责搭棚修葺工作，因而仁杰反可以居高临下，一睹三十六房练功全貌，从中习武达三年之久。工程完毕，三德遂驱逐仁杰出寺，仁杰深感不平。但他却不知道自己不知不觉间已练成少林武功，惩恶扬善，故得“少林搭棚大师”之美名。
Shaanxi Province
Password length cannot be less than 6 bits.
他心中掂掇：难道这些人答得太不像样，所以将军不高兴？小葱静静地翻阅答卷。
影片以一段尘封的魔教教主炼尸往事拉开序幕，竹马恋人再度相遇不料已侠魔相隔。此时，女魔头为非作歹，蛊惑人间，正义联盟乘势集结，逆势改命。侠魔大战阴阳对决，逼真特效万剑齐发，炼尸过程震撼观众，离奇故事曲折动人，忘川之情感怀至深，致胜时刻鹿死谁手！
一个处于两军交战前线的兵家必争之地，战火硝烟自然少不了，又何谈恢复繁荣呢？当然这些都是后话。
Each object has its corresponding state, and each state corresponds to some corresponding behaviors. If an object has multiple states, there will be many behaviors. Then the judgment of these states and the behavior completed according to the states will lead to multiple conditional statements, and if a new state is added, the existing code needs to be changed. This kind of design obviously violates the principle of opening and closing, and the state mode is used to solve such problems.
嗜酒如命，吊儿郎当，死不要脸，与大侠完全不搭边，这是这部电影中，令狐冲给人最直观的印象。
萝苹原以为自己是位孤儿，受不了姑婆的虐待逃离家里。一心前往与父亲的小木屋在街上流浪遇到一对毛和老鼠汤姆和杰瑞患难见真情.他们从原来的排诉到后来的携手合作帮萝苹找到了父亲。
陈毅市长，电影名，著名剧作家沙叶新所著的话剧，1981年由上海电影制片厂搬上银幕；这部电影主要剧情为：1949年5月，上海解放后，陈毅（1901—1972）同志带着满身的战火硝烟出任新中国首任上海市长，当时的旧上海，满目疮痍，积难重重，工厂倒闭，商店关门，粮煤奇缺，失业人口剧增……刚解放的上海确实是个烂摊子；陈毅同志以对党对革命事业的无比忠诚，依靠工人阶级、革命干部和知识分子，团结民族资产阶级，正确地执行党的方针政策，大刀阔斧地开展工作；在短短的一年时间里，陈毅为上海的复兴与发展打开了一个新局面。
明万历年间，朝廷内忧外患不断，古龙镇上一家名为飞刀门的武馆也由于战乱而日渐萧条，师父老李飞刀和两个关门弟子--万里风和牛大春，一起过着不问世事的平静日子。好景不长，老李飞刀的结拜兄弟，起义军领袖郭靖明将女儿郭盈盈托付给老李飞刀照顾，与此同时老李飞刀青梅竹马的师妹，已被皇帝选为贵妃的牛婉君，也由于后宫斗争，带女儿芊芊和太监小顺子到飞刀门避难。这些人同在一个屋檐下却有着相反的立场，老李飞刀一边努力化解双方的隔阂，一边又要保护师妹不受皇后爪牙的袭击，牛贵妃在亲历了老李飞刀为自己所做的一切之后，与昔日的师兄再续前缘。二十年一度的华山论剑，郭靖明与朝廷的夏将军双双前来，意欲借华山论剑之机拉拢武林中人为自己效力，中途却传来倭寇入侵的消息，起义军与朝廷官兵尽弃前嫌，共御外敌，老李飞刀以盟主的身份组织武林人士协助官军，朝廷表彰其功绩，飞刀门被御封“武林第一门”。
陈世迅是个学企业管理的大学毕业生，在北方小城市里一直都郁郁不得志。在妻子秦海莲的鼎力支持下，陈世迅到东海参股一个保健公司的投资，没想到被骗走了全家十几年的积蓄。他只好靠顶替别人开出租车为生。在一次车祸中，陈世迅意外地救了一个叫龚杼丽的女孩子。龚杼丽是希翼集团企业的副总裁，而她的父亲是这个拥有数亿资产的民营企业的总裁。秦海莲一家还在期待着陈世迅能够把家里人接到东海去，然而陈世迅失踪了。秦海莲和陈母突然联系不到陈世迅，电话打不通，信件没有，陈世迅好像在这个世界彻底消失了。秦海莲十分担忧陈世迅的安全，来到东海一边打工，一边寻找自己的丈夫。然而秦海莲常常遇到莫名其妙的各种危险。一次几首被人推入了地铁；一次家里的煤气突然被人打开；一次住处突然着火，面对出现的这一切，秦海莲苦思不解？丈夫不见了，工作生活都这么不顺，自己到底应该怎么办？
Public Object first ();
十年前，东京出现了一个不能解释的领域。从那片领域走出的人获得了一种特殊的超能力——可以随意夺取他们的性命。却如恶魔般从此失去了梦与心。那片神秘的区域被叫做地狱门，而那些因此获取超能力的人被叫做契约者。美国的CIA，英国的MI6，日本的警视厅统统对神秘的地狱门进行了调查研究，甚至那个庞大的神秘组织潘多拉也开展行动，妄图消灭契约者们。知道真相的契约者们则团结在一起进行对抗。而另一方面，有着“黑之死神”之名的黑（木内秀信 配音）接受命令执行着组织的任务，同时也一直在寻找5年前失踪的妹妹。在执行任务的过程中黑偶遇之前的恋人琥珀（川上伦子 配音），发现眼前此人似乎隐藏着一些不为人知的秘密。
Recipient of the 2007 Golden Globe Award for Best Drama Television Series and multiple Emmy nominations, including Outstanding Drama Series for the past two years, "Grey's Anatomy" returns to the ABC Television Network for its fifth season.Is "happily ever after" possible for Meredith Grey and Derek "McDreamy" Shepherd? With Meredith experiencing a breakthrough in therapy - the realization that she and Derek can be extraordinary together, rather than ordinary apart -- she and Derek now face the highs and lows of being a committed couple.Continuing their first year as residents at Seattle Grace Hospital, Meredith, Cristina Yang, Izzie Stevens and Alex Karev have interns of their own to mentor, including Meredith's half-sister, Lexie Grey. Lexie has become a roommate and confidante to George O'Malley, who, after divorce with Callie, a breakup with Izzie, and learning that he failed his residency test by only one point, is striving to get both his professional and personal life back on track.After attending to his girlfriend Rebecca's mental illness on his own, and revealing that he had gone through this with his own mother, Alex finds solace in Izzie's arms. Alex must continue through this difficult time, whether or not Izzie remains by his side.Cristina, having finally won out over her tough-as-nails mentor, Erica, is back on track as a surgeon - but is there a chance for new love in her life as well?With the encouragement of Mark "McSteamy" Sloan, Dr. Callie Torres has taken a chance on love with cardiothoracic surgeon, Erica Hahn; now, she and Erica must figure out what happens after the first kiss.Overseeing the residents is the no-nonsense Chief Resident, Miranda Bailey. Facing marital troubles and the difficulty of balancing her work and personal life, Bailey has handed her responsibilities as head of the free clinic over to Izzie. Also striving for balance is Chief of Surgery, Richard Webber, who has reunited with his estranged wife, Adele.The doctors of Seattle Grace Hospital deal with life-or-death consequences on a daily basis - it's in one another that they find comfort, friendship and love. Together they're discovering that neither medicine nor relationships can be defined in black and white. Real life only comes in shades of grey."Grey's Anatomy" stars Ellen Pompeo as Meredith Grey, Patrick Dempsey as Derek Shepherd, Sandra Oh as Cristina Yang, Katherine Heigl as Isobel "Izzie" Stevens, Justin Chambers as Alex Karev, T.R. Knight as George O'Malley, Chandra Wilson as Miranda Bailey, James Pickens, Jr. as Richard Webber, Sara Ramirez as Callie Torres, Eric Dane as Mark Sloan, Chyler Leigh as Lexie Grey, and Brooke Smith as Erica Hahn.
送别的机场，可欣尽量平静的和范裔风告别，两个人相互交换项链，也许这便是将两个人注定分离的开始。
This class can meet the basic requirements, but if we put a class like this without thread safety protection into a multi-threaded environment, there will definitely be problems. How to solve them? The first thing we think of is adding the synchronized keyword to the getInstance method, as follows:
