C ++和PHP与C＃和Java - 结果不相等

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问题描述

我在C＃和Java中发现了一些奇怪的东西。
让我们来看看这个C ++代码：

I found something a little strange in C# and Java.Let's look at this C++ code:

#include <iostream>
using namespace std;

class Simple
{
public:
    static int f()
    {
        X = X + 10;
        return 1;
    }

    static int X;
};
int Simple::X = 0;

int main() {
    Simple::X += Simple::f();
    printf("X = %d", Simple::X);
    return 0;
}

在控制台中你会看到X = 11（。

In a console you will see X = 11 (Look at the result here - IdeOne C++).

现在让我们看一下C＃上的相同代码：

Now let's look at the same code on C#:

class Program
{
    static int x = 0;

    static int f()
    {
        x = x + 10;
        return 1;
    }

    public static void Main()
    {
        x += f();
        System.Console.WriteLine(x);
    }
}

在控制台中你会看到1（不是11！）（看看这里的结果 -
我知道你现在在想什么 - 这怎么可能？，但是让我们转到下面的代码。

In a console you will see 1 (not 11!) (look at the result here - IdeOne C#I know what you thinking now - "How that is possible?", but let's go to the following code.

Java代码：

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
    static int X = 0;
    static int f()
    {
        X = X + 10;
        return 1;
    }
    public static void main (String[] args) throws java.lang.Exception
    {
        Formatter f = new Formatter();
        f.format("X = %d", X += f());
        System.out.println(f.toString());
    }
}

结果与C＃相同（X = 1，查看结果）。

Result the same as in C# (X = 1, look at the result here).

最后一次让我们来看看PHP代码：

And for the last time let's look at the PHP code:

<?php
class Simple
{
    public static $X = 0;

    public static function f()
    {
        self::$X = self::$X + 10;
        return 1;
    }
}

$simple = new Simple();
echo "X = " . $simple::$X += $simple::f();
?>

结果为11（查看结果）。

Result is 11 (look at the result here).

我有一点理论 - 这些语言（C＃和Java）正在堆栈上制作静态变量X的本地副本（他们是否忽略静态关键字？）。这就是为什么这些语言的结果是1的原因。

I have a little theory - these languages (C# and Java) are making a local copy of static variable X on the stack (are they ignoring the static keyword?). And that is reason why result in those languages is 1.

这里有人，还有其他版本吗？

Is somebody here, who have other versions?

ass

C ++和PHP与C＃和Java - 结果不相等

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