C++怎么开始写啊？

[adi]

如题。

[krerix]

文档说明

[eternalee]

#include <iostream>

void main(void)
{
cout<<"Hello,World!"<<endl;
}

[cowputer]

大家好，
我想应该是先读读一些代码就会知道了
如#include #<iostream.h>
void main()
{
int x,y,z;*/定义三个变量x,y,z/*
x=3;*/给x赋值3/*
y=4;*/给y赋值4/*
z=x+y;*/把x和y的和赋给z/*
cout<<z<<endl;*/输出z的值/*

}
程序结束，
这大概是最简单的，
不知可懂了没？

[间谍]

到底void main()是标准的写法还是main()是标准的写法呀?

[djwinter]

void main()

[lzumcj]

c++中main（）不是最佳方案，会有waring message。因为c++是强制型语言
所以建议写成：return_type main(){ },如：
void main(){ }
int main(){ }
等。。。

[liuer]

强烈郑重庄严隆重推荐使用：void main()

[wondful]

main()也一样，缺省嘛

[davidlxm]

class class_name public : ....
{
};
不然用C算了。

[瑶瑶爸爸]

cout<<"Hello,World!"<<endl;

[albertlee]

天那。

[cowputer]

初学c时都是先用main（）
而初学c++时都是先用void main（）
因为主函数也有返回值

[QXLEE]

好像同意用void的更多，我同意

[swat]

用笔,或用键盘,真笨,这还用人教!

[fiveyes]

找本全国计算机等级考试的二级教程(C语言版)，然后在互联网上(如果你用来学习的那台电脑能上网的话)以Turbo为关键字搜一个Turbo C2.0版，下载。剩下的任务就是对着书逐字逐句逐章逐节逐题逐答案的啃下来。
谈到C++(终于说到C++了)，当你找到一本C++的入门教程的时候，会发现它与C是那么的相似，据说当初给C++命名的时候，有人就建议叫“含有类的C”。
不过这些都不是关键，学好C++，功夫在C++外，或者说，程序员的主要学习内容不是编码。据说在软件工程中，编码的比重顶多占到30%，软件结构的设计更重要，软件的总体设计是最重要的，在总体设计之前的可行性研究及需求分析是最最重要的，软件完成之后的测试维护是最最最重要的。

[TopCat]

标准C++使用int main()，贴一段Bjarne Stroustrup的言论（不翻了，没时间）：

Can I write "void main()"?
------------------------------------
The definition
void main() { /* ... */ }

is not and never has been C++, nor has it even been C. See the ISO C++ standard 3.6.1[2] or the ISO C standard 5.1.2.2.1. A conforming implementation accepts
int main() { /* ... */ }

and
int main(int argc, char* argv[]) { /* ... */ }

A conforming implementation may provide more versions of main(), but they must all have return type int. The int returned by main() is a way for a program to return a value to "the system" that invokes it. On systems that doesn't provide such a facility the return value is ignored, but that doesn't make "void main()" legal C++ or legal C. Even if your compiler accepts "void main()" avoid it, or risk being considered ignorant by C and C++ programmers.
In C++ main() need not contain an explicit return statement. In that case, the value returned is 0, meaning successful execution. For example:

#include<iostream>

int main()
{
std::cout << "This program returns the integer value 0\n";
}

Note also that neither ISO C++ nor C99 allows you to leave the type out of a declation. That is, in contrast to C89 and ARM C++ ,"int" is not assumed where a type is missing in a declaration. Consequently:
#include<iostream>

main() { /* ... */ }

is an error because the return type of main() is missing.

再贴一段这位“C++之父”的“非常简单的小程序”的写法：

How do I write this very simple program?
---------------------------------------------
Often, especially at the start of semesters, I get a lot of questions about how to write very simple programs. Typically, the problem to be solved is to read in a few numbers, do something with them, and write out an answer. Here is a sample program that does that:
#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;

int main()
{
vector<double> v;

double d;
while(cin>>d) v.push_back(d); // read elements
if (!cin.eof()) { // check if input failed
cerr << "format error\n";
return 1; // error return
}

cout << "read " << v.size() << " elements\n";

reverse(v.begin(),v.end());
cout << "elements in reverse order:\n";
for (int i = 0; i<v.size(); ++i) cout << v[i] << '\n';

return 0; // success return
}

Here are a few observations about this program:
This is a Standard ISO C++ program using the standard library. Standard library facilities are declared in namespace std in headers without a .h suffix.
If you want to compile this on a Windows machine, you need to compile it as a "console application".
Yes, main() returns an int.
Reading into a standard vector guarantees that you don't overflow some arbitrary buffer. Reading into an array without making a "silly error" is beyond the ability of complete novices - by the time you get that right, you are no longer a complete novice. If you doubt this claim, I suggest you read my paper "Learning Standard C++ as a New Language", which you can download from my publications list.
The !cin.eof() is a test of the stream's format. Specifically, it tests whether the loop ended by finding end-of-file (if not, you didn't get input of the expected type/format). For more information, look up "stream state" in your C++ textbook.
A vector knows its size, so I don't have to count elements.
for reading in strings, see How do I read a string from input?.
For more examples of how to use the standard library to do simple things simply, see the "Tour of the Standard Library" Chapter of TC++PL3 (available for download).

希望有一点帮助。谢谢！

[Herakles]

推荐你一本书《C++面向对象教程》。

[genius007]

哈哈，按书写，哈哈

[qsyang]

up

[a_programer]

没有事做的时候，多看看书。