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:
为了准确、生动地塑造好这群改变中国近代历史的“红色青春”人物，导演嘉娜·沙哈提、总编剧黄晖搭档领衔主创，柳桦、杨弘和叶牮组成编剧团队，侯京健、刘丛丹、薛皓文、夏德俊、林旭等联袂主演。[/cp]
The newspaper said: "The total number of cancer deaths in the United States showed a downward trend for the first time in 2005." "Cancer is a chronic disease that can be treated, controlled and even cured." In the past, it was believed that cancer would lead to death, and it would take less than three months. Now it is believed that cancer is a chronic disease that can be treated, and the treatment method will change with the change of understanding. The decline in the death rate of cancer patients in turn proves that this change of understanding is close to the right direction. Western medicine came from the West. At present, the number of cancer survivors in the United States is 1/29 of the total population, while that in Shanghai is only 1%, which is far from other places. This shows that Shanghai's understanding and treatment of cancer are still shrouded by the shadow of past mistakes. Many innocent lives still die under the wrong medical understanding and medical methods.
Point out the aligned grid and do not align the grid.
I don't care whether you are Baidu's written examination or Ali's or Tencent's pen examination questions. My side is collectively referred to as the WrittenTest. Then your company has different pen examination questions, which will be implemented by subclasses. No matter how the parent class method is implemented, I don't care what the pen examination questions are. The code changes to the following:
烹饪天才星野光子（天海佑希饰）在银座著名三星法国餐厅担任主厨，但因她过于追求料理水准，完全不考虑成本，惨遭解雇。暂时无法在其他餐厅工作的星野，参加了一档制作营养午餐的电视节目。成本和营养的要求更加严苛，屡屡碰壁的星野却越挫越勇，决心把营养午餐也做成米其林三星水准。
"Yes, Common carnivores, Whether it's a dog, Wolf, or the dog teeth of lion and tiger, They are all tapered sections, With a tip in the front, But this kind of thing is different, All of their teeth are the same, All of them are inverted triangles, And very thin, Both sides are like knives, It was all 'open-edged'. It was very sharp and very hard. When I pried its mouth with a dagger at that time, after priing it open, I could find many thin but obvious scratches on the blade of the dagger in the face of the sun. The dagger I used was made of steel. It was really surprising to me that the teeth could leave such marks on it. "Zhao Mingkai said.
王母（王少梅 饰）容不得牵牛星（黄宗毅 饰）与织女星（严凤英 饰）的两情相悦。金牛星（王少舫 饰）见机出来做月老，王母大怒，将牵牛星与金牛星一同打入凡尘。织女星则被关入云房，失去人身自由，每日望月空叹，好不凄凉。落入凡间的牵、金二星化身为牛郎和老牛，整日里风餐露宿，遍尝劳作艰辛。一日，织女有幸随王母出巡凡界，经金牛牵线，与牛郎栖身人间，过起男耕女织的快乐光景，不久，还诞下一双儿女。出巡归来不见了织女，王母心生恼恨，厉令天兵天将下凡捉拿。落入凡尘的牛郎织女怎对抗得了天上的神仙......
在西南战区R集团军组织的一场常规演习中。按照演习“想定”的规定，担任“红方”的A师必胜，担任“假设敌人”的蓝方C师必败。但“蓝方”利用他们自筹资金建立起来的高技术战场监控系统发现了“红方”攻击中的漏洞，决定打破原有的演习规则，给训练注入新的活力。他们趁夜插入“敌后”，不仅使红方的正面攻击扑空，还成功地占领了“红方”师指挥部......
书生窦天章上京赶考，临行时将独生女儿窦娥托付给蔡婆婆，窦娥与蔡公子完婚。窦娥命苦，婚后不久，蔡公子病逝，窦娥与婆婆相依为命。蔡婆婆靠放些债度日，赛卢医借钱不还，蔡婆婆上门讨债，赛卢医欺她孤儿寡母想要赖账，并欲加害蔡家婆婆，幸被邻居张驴儿相救。张驴儿父子乃市井小人，见到窦娥貌美，便生歹意，欲图谋不轨，张驴儿欲娶窦娥为妻，被窦娥严词拒绝。蔡婆婆一气之下卧床不起。张驴儿逼婚不成，恼羞成怒，与赛卢医合谋，企图毒死蔡婆婆，霸占窦娥。不料，张驴儿之父嘴馋，误食了张驴儿给蔡婆婆做的放了毒药的汤，中毒身亡。 张驴儿恶人先告状，并贿赂贪官，告窦娥害死蔡婆婆。贪官姚杭对窦娥严刑拷打，并以蔡婆婆相逼。窦娥为救婆婆性命，被迫屈招，身陷囹圄...
他明显地觉得，此刻的越军比数十年前的秦国边军战斗力更强，更加可怕……当年蒙恬却匈奴七百余里，那么今天呢？匈奴岂非要退却千里？六七万匈奴大军在的顷刻间陷入悲惨地狱之中，死伤无数，右贤王在死命拼杀之后勉强突围。
《天国餐馆》每集正剧之后的番外。
刘井儿舔舔嘴唇。
女孩承诺为他再存活二十四个月，而一个承诺给男孩带来心灵的重生，也为他带来了命运的血残……
我跟你说，我哥哥姐姐都很好的……遂跟他说起张家的兄弟姐妹，等胖婶和白果端粉丝汤进来的时候，就见两人都趴在桌上，用手撑住下巴，相对轻声说笑呢。
哼，徐荣这只老狗，阳奉yīn违，暗怀鬼胎，今日刚刚找人与我接触，说是想要归顺大王，还要献上女儿给大王。
Although the above pop-up code has completed the effect of creating pop-up windows using single mode, the code is not universal. For example, the above is the code for completing pop-up windows. What if we need an iframe on the page in the future? Do we need to rewrite a set of code to create iframe? For example, create an iframe as follows:
回头真中了，那才是惊喜。
