I was writing a program in C++ to find all solutions of a b = c , where a , b and c together use all the digits 0-9 exactly once. The program looped over values of a and b , and it ran a digit-counting routine each time on a , b and ab to check if the digits condition was satisfied. ...

...or other builtins) directly. It often makes no sense, because what you actually want to do is implement the interface of a dict. And that is exactly what ABCs are for. share | improve this answer ...

... The way timeit works is to run setup code once and then make repeated calls to a series of statements. So, if you want to test sorting, some care is required so that one pass at an in-place sort doesn't affect the next pass with already sorted data (that, of course, would make the Timsort reall...

...as some other model evaluation criteria. If you want the stuff like in Akavall's answer, statsmodels has some more R-like diagnostics. – djs Mar 17 '16 at 18:56 ...

... Basically you need to use the function htmlspecialchars() whenever you want to output something to the browser that came from the user input. The correct way to use this function is something like this: echo htmlspecialchars($st...

...on of objects. The exact type isn't important. From it I want to extract all the unique pairs of a pair of particular properties, thusly: ...

How can I remove all characters except numbers from string? 15 Answers 15 ...

...编译的或官方提供的二进制版本，可以略过此步。 接着下载一份和系统MySQL版本一致的MySQL源代码和HandlerSocket源代码： mysql-5.1.37.tar.gz ahiguti-HandlerSocket-Plugin-for-MySQL-1.0.6-76-gf5f7443.tar.gz shell> tar zxf mysql-5.1.37.tar.gz shell> tar zx...

...t's clear what a metaclass is , there is an associated concept that I use all the time without knowing what it really means. ...

... a True In your case, the second test only works because Python caches small integer objects, which is an implementation detail. For larger integers, this does not work: >>> 1000 is 10**3 False >>> 1000 == 10**3 True The same holds true for string literals: >>> "a" i...