随笔分类 - misc
摘要：An empty Bloom filter is a bit array of m bits, all set to 0. There must also be k different hash functions defined, each of which maps or hashes some
阅读全文
posted @ 2022-01-24 22:31
华容道专家
摘要：Unique items can be difficult to count. Usually this means storing every unique item then recalling this information somehow. With Redis, this can be
阅读全文
posted @ 2022-01-24 22:22
华容道专家
摘要：啥是Reflection? Java Reflection is a process of examining or modifying the run time behavior of a class at run time. The java.lang.Class class provides
阅读全文
posted @ 2022-01-23 09:39
华容道专家
摘要：证明ax的导数后令a等于e即可。 链接 后面那个极限为啥是logea ? 链接 证明在比较靠后的地方。 怎么证明: 而不是用"根据定义"蒙混过去？第二个重要极限的证明 e怎么出来的_p312011150的博客 Squeeze theorem也叫夹逼定理，两面夹法则、三明治定理等。有没有别的证明方法？
阅读全文
posted @ 2022-01-22 17:15
华容道专家
摘要：sin(x+d) - sin(x) = sin(x)cos(d) + sin(d)cos(x) - sin(x) = sin(x)[1 - cos(d)] + sin(d)cos(x) sin(d) / d的极限是1比较容易蒙混过关。两个都很小的数相除。[证明] d趋近0时cos(d)趋近1， 1
阅读全文
posted @ 2022-01-22 09:12
华容道专家
摘要：Transmeta's Crusoe microprocessor is a full, system-level implementation of the x86 architecture, comprising a native VLIW (Very Long Instruction Word
阅读全文
posted @ 2022-01-21 16:11
华容道专家
摘要：Database of Databases - OceanBase (dbdb.io) OceanBase is a distributed, scalable, shared-nothing relational DBMS developed by Alibaba. The goal of Oce
阅读全文
posted @ 2022-01-19 22:32
华容道专家
摘要：y=f(x)=x2, 求f'(x). 直线的斜率k=(y1-y0)/(x1-x0)=((x+d)2 - x2) / (x+d - d) = (2xd + d2) / d = 2x + d = 2x d非常小，无限接近于0，可以被忽略掉。x很大时xd能不能被忽略掉？反正xd/d总等于x。长得像近似解却
阅读全文
posted @ 2022-01-19 13:38
华容道专家
摘要：应为导数、积分和极限; derivative, integral and limit. Bertrand Arthur William Russell, 3rd Earl Russell OM FRS was a British polymath. As an academic, he worked
阅读全文
posted @ 2022-01-19 11:11
华容道专家
摘要：我是个爱攒钱的闲人+非穷人，一直用i3-370m码字看视频，我觉得性能完全够用，没必要换，省下钱来多出去旅游几次也是极好的。 i3-370M, Q3'2010首发，32nm, 2 Core 4 Thread, 2.4G主频, 3MB cache; i5-9500, Q2'2019, 14nm, 6C
阅读全文
posted @ 2022-01-17 12:04
华容道专家
摘要：这事和IBM有关。Intel had introduced the first x86 microprocessors in 1978. In 1981, IBM created its PC, and wanted Intel's x86 processors, but only under th
阅读全文
posted @ 2022-01-17 10:59
华容道专家
摘要：Understanding Quake’s Fast Inverse Square Root – BetterExplained 在某个帖子里我放过厥词"Quake判断某个整数是不是平方数"。说错了。判断是不是平方数步长为2n+1一点都不高档；输入为32位时，16步可以判断出。 该文说到: Floa
阅读全文
posted @ 2022-01-15 11:22
华容道专家
摘要：function handle_register() { add_user(); send_sms(); // 发送手机短信，耗时5秒 show("注册成功。"); } // 缺点：性急的用户还以为注册失败。 function handle_register() { add_user(); // p
阅读全文
posted @ 2022-01-13 16:54
华容道专家
摘要：【字节跳动】2019笔试题--豆油瓶_Mart1nn的博客 题目：抖音中每两个用户之间互动超过3次即互为豆油瓶，若用户1与用户2互动超过3次，用户2又与用户3互动超过三次，则用户1与用户3也为豆油瓶。且用户不能与自身互动（即a[i][i] = 0，i=0,1,2,3…）例1：输入：30 2 42 0
阅读全文
posted @ 2022-01-13 10:48
华容道专家
摘要：有一集《生活大爆炸》，字幕组把every 11 days翻译成每隔11天，我认为不对: every day - 每天 every two days = every other day AB AB AB, A做B不做，隔1天。every day隔0天 every 11 days. 123456789A
阅读全文
posted @ 2022-01-12 22:06
华容道专家
摘要：也许你看英文版的密码学资料有困难，1. 密码学确实复杂; 2. 不是你英语不够好: stackoverflow上也有老外推荐human readable的资料。 本帖如题，human readable绝无问题，准确性就差点意思，甚至可能有错。 每个人都在和密码与证书打交道，比如email账号有密码，
阅读全文
posted @ 2022-01-12 11:49
华容道专家
摘要：使用openssl api编程 - bw_0927 - 博客园 TLS1.2协议设计原理 - 杰哥很忙 - 博客园 OpenSSL是用于安全通信的最著名的开放库。GNS TLS只支持TLS 1.0和SSL 3.0。Mozilla NSS比OpenSSL大，并且需要外部库，而OpenSSL是自包含的。
阅读全文
posted @ 2022-01-12 00:18
华容道专家
摘要：朗文词典:pre-empt or preempt:1. make what sb has planned to do or say unnecessary or ineffective by saying or doing sth first2. replace a television show
阅读全文
posted @ 2022-01-11 16:26
华容道专家
摘要：ISA - Instruction Set Architecture. RISC - Reduced Instruction Set Computer. 居然没有学gcc改称GNU Compiler Collection, 原名/大家都觉得: GNU C Compiler. 因为：There are
阅读全文
posted @ 2022-01-10 16:52
华容道专家
摘要：一本讲FPGA的书里说：Because of complexity, the division operator cannot be synthesized automatically. We use an FSMD to implement the long-division algorithm
阅读全文
posted @ 2022-01-09 20:08
华容道专家
浙公网安备 33010602011771号