====指针运算＝＝
＃i nclude "stdafx.h"
＃i nclude "iostream"
＃i nclude "string"
using namespace std;

int main()
{
 int i[5]={1,2,3,4,5};
 int *p=i;
 cout<<*p<<endl;
 p++;
 cout<<*p<<endl;
 p+=3; //注意不要越界
 cout<<*p<<endl;
 p-=2;
 cout<<*p<<endl;
 return 0;
};
＝＝＝＝＝＝指针与常量限定符＝＝
＃i nclude "stdafx.h"
＃i nclude "iostream"
＃i nclude "string"
using namespace std;

int main()
{
 int k[2]={1,2};
 const int *i=k;
 i++;
 cout<<*i<<endl;
 *i=5; //error 指针常量不能改值
 return 0;

};
＝＝＝＝＝＝＝＝＝
＃i nclude "stdafx.h"
＃i nclude "iostream"
＃i nclude "string"
using namespace std;

int main()
{
 int k[2]={1,2};
 int* const i=k;
 //i++; //error const修饰的指针本身
 cout<<*i<<endl;
 *i=5;
 cout<<*i<<endl;
 return 0;

};
＝＝＝＝＝＝指针与数组＝＝＝
＃i nclude "stdafx.h"
＃i nclude "iostream"
＃i nclude "string"
using namespace std;

int main()
{
 int k[4]={1,2,3,4};
 cout<<*k<<endl;
 int *p=k;
 p++;
 cout<<*p<<endl;

 p=k+2; //p[2]={3,4} p看成数组
 cout<<p[1]<<endl;

 int i=9;
 p=&i; //p[0]=9 p=9
 cout<<p[0]<<endl;
 return 0;

};
＝＝＝＝＝引用＝＝＝
＃i nclude "stdafx.h"
＃i nclude "iostream"
＃i nclude "string"
using namespace std;

int main()
{
 int i=6;
 int& r=i; //i,r,指向同一空间，r为i的别名或引用
 cout<<i<<endl;
 cout<<r<<endl;
 i++;
 cout<<i<<endl;
 cout<<r<<endl;
 r++;
 cout<<i<<endl;
 cout<<r<<endl;
 return 0;
};
＝＝＝＝＝＝变量引用传递不同指针或引用区别＝＝
＃i nclude "stdafx.h"
＃i nclude "iostream"
＃i nclude "string"
using namespace std;

//传值
void fun1(int i)
{
 i++;
 cout<<i<<endl;
}

//传引用
void fun2(int& i)
{
 i++;
 cout<<i<<endl;
}

//传指针
void fun3(int* i)
{
 if(i)
 {
  (*i)++;
  cout<<i<<endl;
 }
}
int main()
{
 fun1(5);
 //fun2(5); //错误，文字常量不能作为引用
 int i=8;
 fun1(i);
 cout<<i<<endl;

 fun2(i);
 cout<<i<<endl;

 fun3(&i);
 cout<<i<<endl;
 return 0;

};
＝＝＝＝＝＝＝＝＝new/delete操作符＝＝＝
＃i nclude "stdafx.h"
＃i nclude "iostream"
＃i nclude "string"
using namespace std;

int a=0; //全局存储空间

int main()
{
 int b; //栈上空间
 int *c=new int(0); //堆上空间
 cout<<*c<<endl;
 delete c;
 return 0;
};
＝＝＝＝＝＝＝new操作符的两种用法＝＝＝
//堆上为单独数据类型分配空间、创建单个变量，返回指向创建数据对象的指针
＃i nclude "stdafx.h"
＃i nclude "iostream"
＃i nclude "string"
using namespace std;

struct st
{
 int a;
 char b;
};

int main()
{
 st* pst=new st();
 delete pst;
 return 0;
};
＝＝＝＝
//创建数组连续空间，返回数组首地址。
＃i nclude "stdafx.h"
＃i nclude "iostream"
＃i nclude "string"
using namespace std;

struct st
{
 int a;
 char b;
};

int main()
{
 st* pst=new st[10];
 delete [] pst;
 return 0;
};