The Head Elder of the tropical island of Lagrishan has a problem. A burst of foreign aid money was spent on extra roads between villages some years ag ...
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其他好文 时间:
2020-04-19 10:48:26
阅读次数:
73
https://www.ted.com/talks/emily_esfahani_smith_there_s_more_to_life_than_being_happy00:12 I used to think the whole purpose of life was pursuing happi ...
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移动开发 时间:
2020-04-19 10:46:12
阅读次数:
62
使用的Extjs版本为4.2,示例是官方的版本,对里面的语法进行一句一句的学习研究。可以方便他人,又可以提升自己的理解。里面存在的问题,后期会一步一步改进。也欢迎各位指出。 ...
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Web程序 时间:
2020-04-16 14:57:27
阅读次数:
100
在下面这个表T中,如果执行 select * from T where k between 3 and 5: mysql> create table T ( ID int primary key, k int NOT NULL DEFAULT 0, s varchar(16) NOT NULL DE ...
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其他好文 时间:
2020-04-16 00:44:17
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70
为什么写这个呢?因为在开发管理系统的过程中,会不可避免的对一些css属性进行调整,其次虽然在大学中学过这些东西,但是主业为java后端,这些我当时是的确是聊聊而过了 一、flex布局介绍,代码如下 { display: flex; justify-content: space-between; al ...
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Web程序 时间:
2020-04-15 00:46:31
阅读次数:
71
索引虽好,但也不是无限制的使用,最好符合一下几个原则 1) 最左前缀匹配原则,组合索引非常重要的原则,mysql会一直向右匹配直到遇到范围查询(>、<、between、like)就停止匹配,比如a = 1 and b = 2 and c > 3 and d = 4 如果建立(a,b,c,d)顺序的索 ...
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其他好文 时间:
2020-04-14 19:03:11
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97
find the phase difference between two singnals matlab code % phase lag of sine and cosine function % https://www.mathworks.com/help/signal/ug/cross-co ...
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其他好文 时间:
2020-04-13 22:56:11
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81
Problem : The Hamming distance between two integers is the number of positions at which the corresponding bits are different. Now your job is to find ...
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其他好文 时间:
2020-04-13 12:22:42
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64
Problem : A sequence of number is called arithmetic if it consists of at least three elements and if the difference between any two consecutive elemen ...
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其他好文 时间:
2020-04-12 13:58:48
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67
where (条件1)and (条件2 or 条件3 or 条件4) = where (条件1 and 条件2)or (条件1 and 条件3) or (条件1 and 条件4) 结果 是这样的 WHERE ( birthdate between ? and ? and username like ...
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其他好文 时间:
2020-04-08 22:36:00
阅读次数:
274