http://poj.org/problem?id=1269Time Limit:1000MSMemory Limit:10000KTotal Submissions:10379Accepted:4651DescriptionWe all know that a pair of distinct p...
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其他好文 时间：
2014-07-22 22:53:16
阅读次数：
314
Given a set of distinct integers,S, return all possible subsets.Note:Elements in a subset must be in non-descending order.The solution set must not co...
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其他好文 时间：
2014-07-21 14:11:16
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151
Additive equationsDescription We all understand that an integer set is a collection of distinct integers. Now the question is: given an integer set...
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其他好文 时间：
2014-07-21 09:35:45
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293
Arithmancy is Draco Malfoy's favorite subject, but what spoils it for him is that Hermione Granger is in his class, and she is better than him at it. ...
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其他好文 时间：
2014-07-21 08:34:51
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639
1.---------------数据库基本操作主键 ： 1.不重复 2.不为NULL外键1.取消重复行(消除完全一样的行，保留一行)select distinct cloumname1,cloumname2 from tablename 2.区间查询(两种是一个意思)select * from e...
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数据库 时间：
2014-07-21 08:30:19
阅读次数：
218
当该字段存在大量值为null或空的记录，容易发生数据倾斜；解决思路：count distinct时，将值为空的情况单独处理，如果是计算count distinct，可以不用处理，直接过滤，在最后结果中加1；如果还有其他计算，需要进行group by，可以先将值为空的记录单独处理，再和其他计算结果进行...
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其他好文 时间：
2014-07-20 22:18:35
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1404
count(distinct key)案例explain select count(distinct session_id) from trackinfo where ds=' 2013-07-21' ;STAGE DEPENDENCIES: Stage-1 is a root stage St.....
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其他好文 时间：
2014-07-20 22:16:56
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347
Sorting It All OutTime Limit:1000MSMemory Limit:10000KTotal Submissions:26876Accepted:9271DescriptionAn ascending sorted sequence of distinct values i...
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其他好文 时间：
2014-07-19 15:03:58
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278
Labeling Balls
Time Limit: 1000MS
Memory Limit: 65536K
Total Submissions: 10178
Accepted: 2815
Description
Windy has N balls of distinct weights from 1 un...
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其他好文 时间：
2014-07-19 02:26:55
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224
B. Suffix Structures
Bizon the Champion isn't just a bison. He also is a favorite of the "Bizons" team.
At a competition the "Bizons" got the following problem: "You are given two distinct w...
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其他好文 时间：
2014-07-18 11:15:25
阅读次数：
252
