何时使用 printf/scanf 与 cout/cin？
我正在使用 MinGW 的 g++ 测试从网上找到的一些片段。这就是 C++ 编译器……为什么它能正确编译 C……为什么人们要把 C 和 C++ 交织在一起。
具体问题是：同时使用C和C++并在g++下编译是否可以。如果答案是肯定的，这会让我的生活变得轻松，因为我不必修改代码。
奇怪的是...为了让一些 C++ 工作，特别是当将字符串传递给 ifstream 构造函数时，它需要一个 C 类型字符串...
我的猜测是，因为 C++ 有时依赖于 C 构造，所以可以编写这两个语言在一起。
不过，就风格而言，您应该选择 cout/cin 或 printf/scanf。
I'm testing some snippets I found off the web using g++ from MinGW. This is the C++ compiler...why then does it correctly compile C....why do people intertwine C and C++.
The concrete question is: Is it O.K. to use both C and C++ and compile under g++. If the answer is yes, this makes my life easy as I do not have to modify the code.
Oddly enough...to get some C++ to work, particularly when passing a string to an ifstream constructor it requires a C type string...
My guess would be that because C++ depends upon C constructs at times is is O.K to write the two languages together.
However as a matter of style you should settle on cout/cin or printf/scanf.
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有一些奇怪的地方需要
char*。您可以使用std::string的.c_str()方法来弥补这一差距。在大多数情况下，C++ 的 C 子集是兼容的。到底如何不兼容在大多数情况下可能并不重要：
http:// /en.wikipedia.org/wiki/Compatibility_of_C_and_C%2B%2B
如果您在 C++ 编译器下编译 C 代码片段，请务必将其更改为在包含中使用“c”lib 格式...例如
#include而不是#include这是不好的做法吗使用C 头文件而不是 C++ 中的 C++ 等效项（例如 stdio.h 而不是 cstdio）？
对于 Bjarne 本人关于为什么要避免 scanf 的合理论证，请查看本文的开头：
http://www.stroustrup.com/new_learning.pdf
使用 iostream 有很多好处也代替 printf：
C++ 中的'printf' 与 'cout'
There are a few oddities where
char*is needed. You can bridge the gap by using the.c_str()method of astd::stringto get one.For the most part, the C subset of C++ is compatible. Exactly how it isn't compatible is not likely to matter for the most part:
http://en.wikipedia.org/wiki/Compatibility_of_C_and_C%2B%2B
If you're compiling snippets of C code under a C++ compiler, be sure to change it to use the "c" lib format in your includes...for example
#include <cstdio>instead of#include <stdio.h>Is it bad practice to use a C header instead of its C++ equivalent in C++ (e.g. stdio.h instead of cstdio)?
For a fairly reasoned argument from Bjarne himself on why to avoid scanf, check out the beginning of this paper:
http://www.stroustrup.com/new_learning.pdf
There are a lot of benefits to using iostreams instead of printf as well:
'printf' vs. 'cout' in C++
C++ 语言继承了 C 的大部分核心功能。这是因为 C++ 派生自 C。C++ 标准通过引用包含了 C 标准的大部分内容。因此，您可以使用 C++ 编译器使用 C 结构、惯用语和范例来编写代码。这样做通常被称为使用 C++“作为更好的 C”。
上面的长短是肯定的，你可以在C++代码中使用
printf。标准明确允许这样做。然而，这样做通常会忽略定义 C++ 的许多功能。我将把这个对话留给另一个问题，但足以说明很多人会简单地告诉您“不要这样做”或“那不是 C++”。这就排除了您可能不想在 C++ 程序中使用 printf 的原因，或者实际上您想要使用的原因。但请放心，这在技术上是允许的。
The C++ language inherits much of its core functionality from C. That's because C++ was derived from C. The C++ Standard includes, by reference much of the C Standard. Therefore you can use the C++ compiler to write code using C constructs, idioms and paradigms. Doing so is often referred to as using C++ "as a better C."
The long and the short of the above is yes, you can use
printfin C++ code. Doing so is explicitly allowed by the Standard.Doing this however will often neglect many of the features that define C++. I'll leave that conversation for another question but suffice it to say that many people will tell you simply "don't do that" or "that's not C++." This sets aside the reasons why you might not want to use
printfin a C++ program or indeed why you would want to. But rest assured that it is technically allowed.是的，可以混合使用这两种语言。这对于最初为 C 的代码很常见，但后来添加了越来越多的 C++ 功能（显然有人在此过程中更改了编译器）。
通常，C 代码将使用 C++ 编译器进行编译和运行。有许多可能的例外，例如在 C 代码中使用
class和virtual等关键字作为事物名称，或者 C 的宽松转换规则。您经常会听到人们说“它们是非常不同的语言”。这是因为您提出的任何编程问题都可能有不同的答案，具体取决于您尝试使用的语言。然而，它们也有很多相似之处和向后兼容性。
Yes, it is fine to mix the two languages. This is common with code that started out as C, but then got more and more C++ features added (obviously somebody changed the compiler along the way).
Generally, C code will compile and run with a C++ compiler. There are many possible exceptions, such as use of keywords like
classandvirtualfor names of things in C code, or C's relaxed casting rules.You will often hear people say "they are very different languages". That's because any programming question you ask probably has a different answer depending on which language you're trying to use. However, there are lots of similarities and backwards compatibility aspects as well.
如果你使用C++，那就使用C++。 (
cin,cout)为什么
fstream需要c字符串也让我困惑。If you use C++, then use C++. (
cin,cout)Why
fstreamtakes c string puzzles me too.