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2010-05-25T14:21:17Z

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2010-05-25T10:29:26Z

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==A static member functions==

<source lang="cpp">#include <iostream>
using namespace std;

class MyClass {
static int count;
public:

MyClass() {
count++;
cout << "Constructing object " <<
count << endl;
}

~MyClass() {
cout << "Destroying object " <<
count << endl;
count--;
}

static int numObjects() { return count; }
};

int MyClass::count;

int main() {
MyClass a, b, c;

cout << "There are now " << MyClass::numObjects() << " in existence.\n\n";

MyClass *p = new MyClass();

cout << "there are now " << MyClass::numObjects() << " in existence.\n\n";

delete p;

cout << " there are now " << a.numObjects() << " in existence.\n\n";

return 0;
}</source>
<pre class=codeResult>Constructing object 1
Constructing object 2
Constructing object 3
There are now 3 in existence.
Constructing object 4
there are now 4 in existence.
Destroying object 4
there are now 3 in existence.
Destroying object 3
Destroying object 2
Destroying object 1</pre>

==name conflicts==

<source lang="cpp">/* The following code example is taken from the book
* "C++ Templates - The Complete Guide"
* by David Vandevoorde and Nicolai M. Josuttis, Addison-Wesley, 2002
*
* (C) Copyright David Vandevoorde and Nicolai M. Josuttis 2002.
* Permission to copy, use, modify, sell and distribute this software
* is granted provided this copyright notice appears in all copies.
* This software is provided "as is" without express or implied
* warranty, and with no claim as to its suitability for any purpose.
*/
#include <iostream>
int C;
class C {
private:
int i[2];
public:
static int f() {
return sizeof(C);
}
};
int f()
{
return sizeof(C);
}
int main()
{
std::cout << "C::f() = " << C::f() << ","
<< " ::f() = " << ::f() << std::endl;
}</source>
<pre class=codeResult>C::f() = 8, ::f() = 4</pre>

==Static method and static variable==

<source lang="cpp">#include <iostream>
using namespace std;
class MyClass {
static int a;
int b;
public:
void set(int i, int j){
a=i;
b=j;
}
static void show();
};
int MyClass::a;
void MyClass::show(){
cout << "This is static a: " << a << endl;
}
int main(void) {
MyClass x, y;
x.set(1,1);
y.set(2,2);
MyClass::show();
y.show();
x.show();
}</source>

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в 14:21, 25 мая 2010

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