15第六周实践——阅读程序

/*

* Copyright (c) 2014, 烟台大学计算机学院

* All rights reserved.

* 文件名称：test.cpp

* 作 者：李晓凯

* 完成日期：2015年 4 月 11 日

* 版 本 号：v1.0

*

* 问题描述：

* 输入描述：

* 程序输出：

*/

(1)代码：

#include <iostream>
using namespace std;
class A
{
public:
A()
{
cout<<"A";
}
~A()
{
cout<<"~A";
}
};
class B
{
A *p;
public:
B()
{
cout<<"B";
p=new A();
}
~B()
{
cout<<"~B";
delete p;
}
};
int main()
{
B obj;
return 0;
}

(2)代码：

#include <iostream>
using namespace std;
class MyClass
{
public:
MyClass(int x=0):i(x)
{
cout<<"C"<<i;
}
~MyClass()
{
cout<<"D"<<i;
}
void SetValue(int val)
{
i=val;
}
int GetVal()
{
return i;
}
private:
int i;
};
int main()
{
MyClass *p[3];
int i;
for (i=0; i<3; i++)
{
p[i]=new MyClass(i);
p[i]->SetValue(p[i]->GetVal()*2);
}
for (i=0; i<3; i++)
delete p[i];
cout<<endl;
return 0;
}

(3)代码：

#include <iostream>
using namespace std;
class B
{
public:
B()
{
cout<<"default constructor"<<endl;
}
~B()
{
cout<<"destructed"<<endl;
}
B(int i):data(i)
{
cout<<"constructed: " << data <<endl;
}
private:
int data;
};
B Play(B b)
{
return b ;
}
int main()
{
B temp = Play(5);
return 0;
}

(4)代码：

#include <iostream>
using namespace std;
class example
{
public:
example()
{
cout<<"Default Constructing! "<<endl;
}
example(int n)
{
i=n;
cout<<"Constructing: "<<i<<endl;
}
~example()
{
cout <<"Destructing: "<<i<<endl;
}
int get_i()
{
return i;
}
private:
int i;
};
int sqr_it(example o)
{
return o.get_i()* o.get_i();
}
int main()
{
example x(10);
cout<<x.get_i()<<endl;
cout<<sqr_it(x)<<endl;
return 0;
}

(5)代码：

</pre><pre name="code" class="cpp">#include <iostream>
using namespace std;
class AA
{
public:
AA(int i,int j)
{
A=i;
B=j;
cout<<"Constructor\n";
}
AA(AA &obj)
{
A=obj.A+1;
B=obj.B+2;
cout<<"Copy_Constructor\n";
}
~AA()
{
cout<<"Destructor\n";
}
void print()
{
cout<<"A="<<A<<",B="<<B<<endl;
}
private:
int A,B;
};
int main()
{
AA a1(2,3);
AA a2(a1);
a2.print();
AA *pa=new AA(5,6);
pa->print();
delete pa;
return 0;
}