c++ 简单程序错误

Question

I have created a file called untitled1.cpp in dev-cpp with the following script:

#include <iostream.h>
using namespace std;
int main(){
    cout << "C++";
    return 0;
}

But the compiler shows errors like:

1 F:\Dev-Cpp\include\c++\3.4.2\backward\iostream.h:31,
from F:\Dev-Cpp\Untitled1.cpp In file included from include/c++/3.4.2/backward/iostream.h:31, from F:\Dev-Cpp\Untitled1.cpp 32:2 F:\Dev-Cpp\include\c++\3.4.2\backward\backward_warning.h #warning This file includes at least one deprecated or antiquated header. Please consider using one of the 32 headers found in section 17.4.1.2 of the C++ standard. Examples include substituting the header for the header for C++ includes, or instead of the deprecated header. To disable this warning use -Wno-deprecated.

What is the error that I have? How do I fix it?

Answer 1

In C++ you import the standard library without using the .h suffix.

#include <iostream>

So your fixed example:

#include <iostream>

int main(int argc, char **argv) {
    std::cout << "C++";
    return 0;
}

Answer 2

Your code is not standard C++. You should say #include <iostream> (no ".h".), Whatever source you have been learning this from is about 25 years out of date. and you should consider getting some more modern material.

(The "iostreams.h" header was part of a very early non-standard library in the early 1990s, and so it's being kept around for "compatibility" reasons, or to catch very inert programmers and give them a helpful hint.)

Answer 3

Use header file as #include<iostream> instead of #include<iostream.h>

Answer 4

Include iostream instead of iostream.h

Answer 5

It says that the header, in this case, iostream.h is deprecated or antiquated. (You only have one header, so that's the one! Just read the error message!)

So you'll have to use iostream , not iostream.h .

Answer 6

This is just a warning.

I think that you could try to include iostream instead of iostream.h in order to fix it.

Answer 7

You've posted the reason in your question already!

This file includes at least one deprecated or antiquated header.

The real question should therefore be: "Which one is antiquated, how do I replace it?", not "What's the error". Answer: Use <iostream> . The <*.h> versions are pre-standard, legacy headers.

So: Read error messages, people.