d********w 发帖数: 363 | 1 品味来了。
Basics and Algorithms
The Five-Minute Rule Ten Years Later, and Other Computer Storage Rules of
Thumb (1997): This paper (and the original one proposed 10 years earlier)
illustrates a quantitative formula to calculate whether a data page should
be cached in memory or not. It is a delight to read Jim Gray approach to an
array of related problems, e.g. how big should a page size be.
AlphaSort: A Cache-Sensitive Parallel External Sort (1995): Sorting is one
of the most essential algorithms in... 阅读全帖 |
|
S****7 发帖数: 9 | 2 【 以下文字转载自 DataSciences 讨论区 】
发信人: SQyue7 (SQ), 信区: DataSciences
标 题: database startup の 广告~ (不是骗子)
关键字: database,high performance
发信站: BBS 未名空间站 (Sun Aug 24 05:03:20 2014, 美东)
小弟我所在的公司叫做 LightMiner Systems,是坐落在Palo Alto的一个小小的
startup
我们的产品是类似 Vertica 的 data analytic platform ,简单来说就是包括一个
database,一个 web based workspace 可以运行 SQL 和 Rstudio,一些重新写的
paralleled machine learning R function
相比 Vertica,我们的 database 做 Query 更快,而且便宜一些(公司目前需要
sales 来做 user case 用于第二轮的 fund raising,所以卖良心价)我手上有公司的
white
pape... 阅读全帖 |
|
S****7 发帖数: 9 | 3 【 以下文字转载自 DataSciences 讨论区 】
发信人: SQyue7 (SQ), 信区: DataSciences
标 题: database startup の 广告~ (不是骗子)
关键字: database,high performance
发信站: BBS 未名空间站 (Sun Aug 24 05:03:20 2014, 美东)
小弟我所在的公司叫做 LightMiner Systems,是坐落在Palo Alto的一个小小的
startup
我们的产品是类似 Vertica 的 data analytic platform ,简单来说就是包括一个
database,一个 web based workspace 可以运行 SQL 和 Rstudio,一些重新写的
paralleled machine learning R function
相比 Vertica,我们的 database 做 Query 更快,而且便宜一些(公司目前需要
sales 来做 user case 用于第二轮的 fund raising,所以卖良心价)我手上有公司的
white
pape... 阅读全帖 |
|
S****7 发帖数: 9 | 4 小弟我所在的公司叫做 LightMiner Systems,是坐落在Palo Alto的一个小小的
startup
我们的产品是类似 Vertica 的 data analytic platform ,简单来说就是包括一个
database,一个 web based workspace 可以运行 SQL 和 Rstudio,一些重新写的
paralleled machine learning R function
相比 Vertica,我们的 database 做 Query 更快,而且便宜一些(公司目前需要
sales 来做 user case 用于第二轮的 fund raising,所以卖良心价)我手上有公司的
white
paper,里面有和其他公司产品比较的 test case。就我看到的数
据,我们比 Vertica 有几百倍的 speedup。
公司十几个人就我是中国人。他们多少喜欢吹,而且我们外包的销售团队都是吹嘘派的
。所以我相信老板是找了差距最大的 test case 写进 white paper。虽然我目前很菜,
很多概念都没搞懂,但如果需要,我会相对客观的提供有用... 阅读全帖 |
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发帖数: 1 | 5 Company: Okta
Location: SF or San Jose
如果感兴趣,请发简历到 [email protected]
https://www.okta.com/company/careers/ga/senior-data-engineer--983309/
Senior Data Engineer
Position Description:
We are looking for an exceptional Senior Data Engineer who is responsible
for designing and developing robust, scalable solutions for large-scale data
infrastructure in a fast-paced agile environment. You will be encouraged to
initiate new projects to collect, store, and analyze data and to partner
with analysts... 阅读全帖 |
|
c******n 发帖数: 710 | 6 My friend's team has multiple openings. The job descriptions are below.
If interested, please send email to e*****[email protected] for refer or apply on
ea.com directly. Thank you.
--------------------------------------------------------------------
New Graduate: Software Engineer - Data Engineering (4284) or Sr. Data
Platform Engineer (8594)
Responsibilities:
• Help define and build a unified data platform across EA, spanning
20+ game studios as data sources
• Develop infrastructure soft... 阅读全帖 |
|
l*n 发帖数: 529 | 7 你提的问题的确涉及到mapreduce vs. analysis的核心:hdfs通用的分布式同数据的结
构化之间的矛盾。如果你的三种分析是独立的,那么你确实要分开run 3个MR的任务,
文件IO的确是要重复3次;如果三个分析的信息是结构化的,那么可以只搞一个复杂点
的MR任务,只做一次文件IO。这时候就变成了程序执行效率 vs. 程序编写效率之间的
矛盾了。
目前解决的方向好像都是在借鉴传统SQL的思路,比如是columnar storage,就是把结
构化信息拆开让不同组分分别存储,需要的时候再聚合,另一个是MR执行的推迟,让
engine对MR任务进行优化。Hive就是把query转成MR任务,有人说他慢就是因为生成的
MR方案以及query和query之间的优化还不够好吧。
word: |
|
m*z 发帖数: 234 | 8 我们公司去年刚上市,上升趋势稳定,总部在Austin。公司员工绝大部分是白人,极少
印度人,当然中国人也极少,我们部门99个员工就我一中国人。现需急聘Data
Engineer若干。
Austin附近有很多湖,有山有水,是德州为数不多的风景好区。还有各种音乐节,平时
夜晚市区都有大量的live music,被誉为Live Music Capital of the World,是coder
不错的定居点。
有兴趣者请把简历寄到 a***************[email protected]
谢谢你的关注。
Position 1 Data Warehouse Engineer
About the Role:
Data is core to our business and future success. Our Data team is looking
for a Data Warehouse Engineer to play a pivotal role in managing and
distributing data. You will collaborate with a multidis... 阅读全帖 |
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s******c 发帖数: 1920 | 9 Map reduce
Or dremel
要点在于把log存成columnar的 便于filter |
|
b**********5 发帖数: 7881 | 10 没说cassandra, hbase有什么重合, 只是一般来说, cassandra/hbase都属于nosql
persistent store,both columnar database。。。
yes redis can be used as persistent store, but it's mostly used as a in
memory cache. so i would consider as in the same category as memcache
btw, i think someone replied that zippydb is not the enterprise redis, it's
something else |
|
|
z******s 发帖数: 322 | 12 看到cobol和mainframe我笑了,这都哪年的老黄历了?记得十年前,银行根本就找不到
会cobol的人,如果你精通cobol,随便找个维护的工作,朝九晚五啥都不干,轻松赚30
-40万。现在还cobol?
这个楼里基本上都是些以讹传讹不知道哪儿整来的信息。哥来给你们科普一下吧,银行
(主要是投行,商业银行就不算了)的IT系统从08年金融危机之后给搅了个天翻地覆,
大量的analytics和control的项目在做,的因为很多东西需要real time的控制和读取,
同时需要极高的可靠性,所以用的很多都是hardcore的技术,像多线程,realtime,
columnar db, distributed cache,都是最最核心的。有些非常贵的软件比如KDB+之类
的,外面根本想用都用不到。外面一堆一堆的所谓web 热门技术,说白了就是跟搬砖差
不多,技术含量跟这些比简直就是天上地下。
当然,也有保守的部门,弄个内部网站几百年不变,这都是enterprise的部分,哪个公
司都有,跟核心不是一回事。除了应用之外,有钱的银行还有更深层的优化,C++之父
离开学校去了哪儿知道?银行。... 阅读全帖 |
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q**d 发帖数: 1470 | 13 好贴。
5年kdb+经验,每天都收到猎头邮件,包裹都是250k+起,可惜咱懒得动,呵呵。
记得刚入职的时候,老板请来某藤校天神级教授给我们(一共3个人)上了一星期的课
,这也是我ID的由来。。。
想不通那些靠刷题进tech然后做螺丝钉给烙印做苦力的人有什么资格看不起投行IT?
每次看到Leetcode一类的东西我就觉得反胃,花时间做这些毫无实用价值的应试题根本
是浪费生命。
我们招人从来不考这些公式化的算法题,而是由组里的每个人自己临时想一道问题,通
常来说只要你确实有kdb/q的开发经验,你根本不用刷题(而且也没地方可刷)就能够
在我们的帮助下轻松搞定。
前不久我们刚录用了个VP级的q dev,包裹给了300k。。。
这个楼里基本上都是些以讹传讹不知道哪儿整来的信息。哥来给你们科普一下吧,银行
(主要是投行,商业银行就不算了)的IT系统从08年金融危机之后给搅了个天翻地覆,
大量的analytics和control的项目在做,的因为很多东西需要real time的控制和读取,
同时需要极高的可靠性,所以用的很多都是hardcore的技术,像多线程,realt... 阅读全帖 |
|
J*****6 发帖数: 107 | 14 Position Overview
As a Data Systems, Server Side Engineer you
will be designing and implementing systems that crunch and process billions
of records a day and make them available in DoubleVerify’s analytics
platform, helping our clients to make smarter decisions that continuously
improve their ad-impression quality. You will develop server side code and
APIs to integrate multiple systems implemented in different technologies.
... 阅读全帖 |
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J*****6 发帖数: 107 | 15 这个公司本身是在新泽西的哦,然后公司规模不是很大,算是中型金融科技公司吧,最
近招挺多人的感觉,工资他们估计能给10,11万的样子。(LZ 知道这个包裹和FLAG 不
能比,但是在大家去 FLAG之前也是得工作累计经验的呢,好机会表错过呢)工作中除
了在家工作,用电话和公司汇报工作外,就是需要有个25%的出差哦,都是在美国境内
出差哦。 平时也不需要去公司。 Visa 要求是只收绿卡,或者公民哦,职位介绍完毕
。
然后来介绍下lz好了,lz是纽约的小猎头,手上职位基本都是金融方面的科技职位哦,
大家如果是H1B的话,我应该有其他职位可以适合大家的呢,最近出来的都是一些前端
职位,有个纽约的startup 招Javascript,很多人面的如火如荼的呢。
大家如果对这个职位感兴趣的话可以发简历给我哦,[email protected]/* */ 可以发到这
个邮箱哦。有任何问题的话大家就留言,或者私信我吧~~
You can work anywhere they want even UK. Requires 25% TRAVEL.
The Consultant... 阅读全帖 |
|
发帖数: 1 | 16 Company: Okta
Location: SF or San Jose
如果感兴趣,请发简历到 [email protected]
https://www.okta.com/company/careers/ga/senior-data-engineer--983309/
Senior Data Engineer
Position Description:
We are looking for an exceptional Senior Data Engineer who is responsible
for designing and developing robust, scalable solutions for large-scale data
infrastructure in a fast-paced agile environment. You will be encouraged to
initiate new projects to collect, store, and analyze data and to partner
with analysts... 阅读全帖 |
|
c******n 发帖数: 710 | 17 My friend's team has multiple openings. If interested, please send email to
e*****[email protected] or apply on ea.com directly.
---------------------------------------------------------------------
New Graduate: Software Engineer - Data Engineering (4284) or Sr. Data
Platform Engineer (8594)
Responsibilities:
• Help define and build a unified data platform across EA, spanning
20+ game studios as data sources
• Develop infrastructure software that slice and dice data, using
Hadoop and Map/... 阅读全帖 |
|
发帖数: 1 | 18 Company: Okta
Location: SF or San Jose
如果感兴趣,请发简历到 [email protected]
https://www.okta.com/company/careers/ga/senior-data-engineer--983309/
Senior Data Engineer
Position Description:
We are looking for an exceptional Senior Data Engineer who is responsible
for designing and developing robust, scalable solutions for large-scale data
infrastructure in a fast-paced agile environment. You will be encouraged to
initiate new projects to collect, store, and analyze data and to partner
with analysts... 阅读全帖 |
|
j****3 发帖数: 2836 | 19 Thanks a lot. Following is the list of evergreen trees allowed in the
community. How much will them cost, roughly? And what does "Gal." and "B & B
" means?
LOW GROWING EVERGREENS
Green Sergeant Juniper 2 Gal. & Up 15" - 18" B & B
Sea Green Juniper 2 Gal. & Up 15" - 18" B & B
Bar Harbor Juniper 2 Gal. & Up 15" - 18" B & B
Andorra Juniper 2 Gal. & Up 15" - 18" B & B
EVERGREENS
Globe Yew 15" - 18" B & B
Hicks Hedge Yew 15" - 18" B & B
Up Right Columnar Yew 36" - Up B & B |
|
s*****3 发帖数: 69 | 20 情况如下,有兴趣请站内联系。
----------------------------------------------------
=Position Overview=
A startup company based in Beijing is recruiting talented engineers to
join its core team, in connection with the development of two systems
for querying big data.
One system is a highly-scalable SQL query engine to query big relations
with bounded resources. The other is a graph query engine based on a new
parallel computation model, to support plug and play of sequential graph
algorithms. The systems have c... 阅读全帖 |
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L*******s 发帖数: 138 | 21 【 以下文字转载自 Working 讨论区 】
发信人: Livernois (Livernois), 信区: Working
标 题: 【招聘】Java Developer [Scottsdale, AZ]
发信站: BBS 未名空间站 (Tue Jun 26 14:07:18 2012, 美东)
发信人: Livernois (Livernois), 信区: JobHunting
标 题: 【招聘】Java Developer [Scottsdale, AZ]
发信站: BBS 未名空间站 (Tue Jun 26 14:06:47 2012, 美东)
公司目前在Arizona的合作项目有以下职位招人,帮办H1b,绿卡
请站内投条联系。谢谢
Overview:
Our client is a fast growing digital marketing media company, is seeking a
mid level Core Java developer to work in a challenging environment
developing high perf... 阅读全帖 |
|
L*******s 发帖数: 138 | 22 公司以下职位招人,帮办H1b和绿卡
有兴趣请站内信联系
We are seeking a mid level Core Java developer to work in a challenging
environment developing high performance real-time data processing
applications. This individual should be a highly motivated and technically
proficient engineer who has 4+ years experience in J2EE design and
development. Someone who is passionate about data and scaling up data
infrastructure.
Overview
* Work on scalable applications with >1,000 requests per second handling
requirement ?
* Work wi... 阅读全帖 |
|
z**********i 发帖数: 12276 | 23 http://www.thedenverchannel.com/weather/4955659/detail.html
SHORT DRIVES FROM THE METRO AREA
•1. Guanella Pass between Grant and the top of the pass -- Take
Highway 285 south from C470 through Conifer and Bailey. At the town of Grant
, head north on the Guanella Pass Scenic and Historic Byway to the top of
the pass. Guanella Pass is closed on the north side of the pass and through
travel is prohibited to Georgetown. The aspens are typically exceptional on
the south side of Guanella Pass, w... 阅读全帖 |
|
h******d 发帖数: 4761 | 24 好东西不敢独享!
全文请看:http://calasf.blogspot.com/
Eastern Sierra & Scenic 395景觀公路 - http://scenic395.com、http://395.com
Sierra Nevada內華達山脈東側稱為Eastern Sierra山脈東側,蒼綠的Inyo National
Forest銀約國家森林中鑲嵌許多晶瑩剔透的湖泊群,恬靜有生氣,層巒疊嶂的Sierra
Nevada山脈暱稱The High Sierra或The Sierra,一般人常會覺得Contiguous United
States美國本土最高聳山峰可能在美國中部,但事實是最西加州Sierra Nevada內華達
山脈的Mt .Whitney惠特尼峰。洛杉磯往北駛入Owens Valley歐文山谷,是美國落差最
高由Owens River歐文河侵蝕而成,穿行谷底的世界級景觀公路Scenic 395,或稱
Eastern Sierra Scenic Byway山脈東側景觀公路,崇山峻嶺兩側聳立,巍峨群山覆滿
白雪、雲霧繚繞,但谷底山清水秀很少有下雪,道路大體寬直... 阅读全帖 |
|
i*******h 发帖数: 1470 | 25 4最有效。。
这个,没有太多实战经验啊,不过据我在天涯长期看帖的理论经验,pill对身体不好,
内分泌失调,发胖,性格变暴躁;condom磨cervical,容易引起columnar ectopy;IUD
的原理是让子宫一直发炎,这个是对身体最不好的,只有最不疼老婆的男人和最不为自
己想的女人才用这个;4应该是最有用的吧,对女性身体最好。。。
还有其他的吗?哦对了有个事后药,那个傻孩子才吃。。。
这个帖子80浏览量了就我一人回,是不是大家都不好意思啊,茫然左看右看一下。。 |
|
|
c*****1 发帖数: 1826 | 27 查了一下,我的这个品种叫scarlet sentinel columnar apple.
怎么知道它可不可以自花授粉?
反正今年光开花没结果,现在猜
可能是这个问题。如果在它树干
上嫁接一个其他
品种的苹果,可不可以解决这个
授粉问题? |
|
e*f 发帖数: 1709 | 28 Google "columnar pine trees near your zip code".
这种树的高度与间距成正比,是非常常见隔离树,长的很快。心急就用这种。 |
|
i***a 发帖数: 11826 | 29 对,Erechtheion庙的人像柱(Caryatids),在古希腊是战败城邦的祭祀妇女。:)
这个城邦在战争中,背叛了雅典投靠敌人,之后雅典血洗了城邦,以妇女和儿童为奴。
后世看来如此优雅的人像柱,在古希腊表达的是对背叛城邦的惩罚。
类似本楼的高卢战士,后世更欣赏雕塑的美。但在古代,都是对败者的刻画。雕塑形象
认真看很残酷,高卢战士形象蛮族垂死,女像站立着永远的抗殿顶~:)贴张大英博物
馆的细节图~
英文reference:
Caryatids: The Form and the Symbol
The sculpted columnar form of the caryatids is named after the women of the
town of Kayrai, a small town near and allied to Sparta. At one point during
the Persian Wars the town betrayed Athens to the Persians. In retaliation,
the Athenians sacked t... 阅读全帖 |
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s**********x 发帖数: 4593 | 30 二、电子系
题目:激光超声机理及技术应用
报告人:张淑仪院士
时间:5月24日上午10时
地点:物理楼356
题目:Dynamics of Josephson vortex lattice in a presence of pancake vortex
lin
es and columnar defects
报告人:Dr.Yu.I.Latyshev俄罗斯科学院无线电工程与电子学研究所
时间:5月25日下午2:30
地点:蒙民伟楼2609
题目:On the mechanism of Josephson vortex lattice melting in Bi-2212
报告人:Dr.V.N.Pavlenko俄罗斯科学院无线电工程与电子学研究所
时间:5月25日下午2:30
地点:蒙民伟楼2609 |
|
|
d***l 发帖数: 48 | 32 Usually, how to characterize the self-assembly structure in solution? Let's
say columnar structure. |
|
D*****l 发帖数: 554 | 33 UW Qbank is a great one. How to make notes from UW? I am lazy and hate
typing. I use TopOCR software and then copy/paste into my word document.
Do you have a better way to do this? If so, please let me know.
The following is the example I just did.
The inner walls of the lesion are most likely lined with:
O A. Glycogen-rich cuboidal epithelium
O B. Columnar mucinous epithelium
O C. Atypical cells forming papillary projections
~ O D. Fibrous and granulation tissue
X O E. Endothelial cells
This C... 阅读全帖 |
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f**d 发帖数: 768 | 34 ScienceDaily (May 1, 2011) — For more than 50 years, a dominating
assumption in brain research was that nerve cells in the cortex of the
brain are organised in the form of microscopically small columns.
Subsequently, it became a textbook standard that connections are created
predominantly between nerve cells within these columns. In a review
article for the journal Frontiers in Neuroscience, Clemens Boucsein
and colleagues from the Bernstein Centers in Freiburg and Berlin show
that this view has... 阅读全帖 |
|
d*2 发帖数: 2053 | 35 http://vision.cloudera.com/impala-v-hive/
by Mike Olson
December 22, 2013
We introduced Cloudera Impala more than a year ago. It was a good launch for
us — it made our platform better in ways that mattered to our customers,
and it’s allowed us to win business that was previously unavailable because
earlier products simply couldn’t tackle interactive SQL workloads.
As a side effect, though, that launch ignited fierce competition among
vendors for SQL market share in the Apache Hadoop ecosystem, w... 阅读全帖 |
|
s**********g 发帖数: 1578 | 36 将要传递的字母交替排成上下两行,再将下面一行字母排在上面一行的后边,从而形成
一段密码。
举例:
TEOGSDYUTAENNHLNETAMSHVAED
解:
将字母分截开排成两行,如下
T E O G S D Y U T A E N N
H L N E T A M S H V A E D
再将第二行字母分别放入第一行中,得到以下结果
THE LONGEST DAY MUST HAVE AN END
.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
第一个游戏: 下面的密码是什么呢??
WLOEOHCDCUECMTTEOELB
.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
那么这个呢? 试一试??
IOUTFSSYINONOUENRSEBS
.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
WIKI read: http://en.wikipedia.org/wiki/Transposition_cipher |
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s**********g 发帖数: 1578 | 37 加密时不一定非用两栏.
如: 篱笆移位法 Rail Fence cipher
密文: WECRLTEERDSOEEFEAOCAIVDEN
W===E===C===R===L===T===E
=E= R=D=S=O=E =E= F=E= A=O=C=
==A===I===V=== D===E===N==
用波浪型排成,
明文: WEAREDISCOVEREDFLEEATONCE (we are discovered flee at once)
《数字城堡》中的一个例子,密文为:
PFEE SESN RETM MFHA IRWE OOIG MEEN NRMA ENET SHAS DCNS IIAA IEER BRNK FBLE
LODI
去掉空格:PFEESESNRETMMFHAIRWEOOIGMEENNRMAENETSHASDCNSIIAAIEERBRNKFBLELODI
共64个字符,以8个字符为一栏,排列成8*8的方阵:
P F E E S E S N
R E T M M F H A
I R W E O O I G
M E E N N R M A
E N E T S H A S |
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s**********g 发帖数: 1578 | 38 将要传递的字母交替排成上下两行,再将下面一行字母排在上面一行的后边,从而形成
一段密码。
举例:
TEOGSDYUTAENNHLNETAMSHVAED
解:
将字母分截开排成两行,如下
T E O G S D Y U T A E N N
H L N E T A M S H V A E D
再将第二行字母分别放入第一行中,得到以下结果
THE LONGEST DAY MUST HAVE AN END
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第一个游戏: 下面的密码是什么呢??
WLOEOHCDCUECMTTEOELB
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那么这个呢? 试一试??
IOUTFSSYINONOUENRSEBS
.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
WIKI read: http://en.wikipedia.org/wiki/Transposition_cipher |
|
s**********g 发帖数: 1578 | 39 加密时不一定非用两栏.
如: 篱笆移位法 Rail Fence cipher
密文: WECRLTEERDSOEEFEAOCAIVDEN
W===E===C===R===L===T===E
=E= R=D=S=O=E =E= F=E= A=O=C=
==A===I===V=== D===E===N==
用波浪型排成,
明文: WEAREDISCOVEREDFLEEATONCE (we are discovered flee at once)
《数字城堡》中的一个例子,密文为:
PFEE SESN RETM MFHA IRWE OOIG MEEN NRMA ENET SHAS DCNS IIAA IEER BRNK FBLE
LODI
去掉空格:PFEESESNRETMMFHAIRWEOOIGMEENNRMAENETSHASDCNSIIAAIEERBRNKFBLELODI
共64个字符,以8个字符为一栏,排列成8*8的方阵:
P F E E S E S N
R E T M M F H A
I R W E O O I G
M E E N N R M A
E N E T S H A S... 阅读全帖 |
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