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Why does isNaN(“ ”) (string with spaces) equal false?
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But parseInt("123abcd") returns 123, which means isNaN(parseInt("123abcd")) will return false while it should return true!
– Pawan Nogariya
Dec 27 '12 at 6:23
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泰迪熊为什么叫泰迪 - 杂谈 - 清泛网 - 专注C/C++及内核技术
...是 San Jose 通过路边 Ask.com 巨大的广告牌抛给我的第一个问题。
广告牌上除了这个问题和巨大的 Ask.com 之外什么也没有。我以前也曾经想过类似的招数，如果我是男生，就把博客里无聊的问题印在T恤上，来钓到好奇心重的女生...
How to initialize a struct in accordance with C programming language standards
...tializer to initialize a structure:
MY_TYPE a = { .flag = true, .value = 123, .stuff = 0.456 };
Edit: Other members are initialized as zero: "Omitted field members are implicitly initialized the same as objects that have static storage duration." (https://gcc.gnu.org/onlinedocs/gcc/Designated-In...
How do I interpret precision and scale of a number in a database?
...efers to the maximum number of digits that are present in the number.
ie 1234567.89 has a precision of 9
Numeric scale refers to the maximum number of decimal places
ie 123456.789 has a scale of 3
Thus the maximum allowed value for decimal(5,2) is 999.99
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MySQL复制的概述、安装、故障、技巧、工具 - 数据库(内核) - 清泛网 - 专注...
...主机名作为名字，如此一来一旦主机名发生改变，就会出问题，所以推荐指定log_bin（从服务器的relay_log存在一样的问题）。
注：sync_binlog，innodb_flush_log_at_trx_commit，innodb_support_xa三个选项都是出于安全目的设置的，不是复制的...
Python-equivalent of short-form “if” in C++ [duplicate]
Is there a way to write this C/C++ code in Python?
a = (b == true ? "123" : "456" )
4 Answers
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Why would I ever use push_back instead of emplace_back?
... will be invalid after the call.
std::vector<int> v;
v.emplace_back(123);
v.emplace_back(v[0]); // Produces incorrect results in some compilers
On one compiler, v contains the values 123 and 21 instead of the expected 123 and 123. This is due to the fact that the 2nd call to emplace_back re...
What is the difference between parseInt() and Number()?
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typeof parseInt("123") => number
typeof Number("123") => number
typeof new Number("123") => object (Number primitive wrapper object)
first two will give you better performance as it returns a primitive instead of an object.
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30岁之后，程序员该向什么方向发展？ - 杂谈 - 清泛网 - 专注C/C++及内核技术
...，脑袋没有那么灵光，没有那么有冲劲了，这也是个人的问题。如果你自己不努力，到多少岁都一样。
以前也有人问我二十几岁再开始编程晚不晚，我的回答是，不晚，什么时候都不晚。
QA&2. 您个人或身边有这样的实例吗？...
How do I check if a C++ std::string starts with a certain string, and convert a substring to an int?
...only match at that position or earlier. For example:
std::string test = "0123123";
size_t match1 = test.rfind("123"); // returns 4 (rightmost match)
size_t match2 = test.rfind("123", 2); // returns 1 (skipped over later match)
size_t match3 = test.rfind("123", 0); // returns std::string::npos (i...