C++操作符new-动态存储空间分配

1         int *p=new int;
2         *p=10;
3         cout<<"p="<<p<<endl;
4         cout<<"*p="<<*p<<endl;
5         delete p;
6         p=NULL;

 1         int n;
 2         cin>>n;
 3         int *p =new int[n];
 4         for(int i=0;i<n;i++)
 5         {
 6                 cin>>*(p+i);
 7                 cout<<*(p+i)<<endl;
 8         }
 9         delete []p;
10         p=NULL;

 1         int n;
 2         cin>>n;
 3         int **p;
 4         p=new int*[3];
 5         for(int i=0;i<3;i++)
 6         {
 7                 p[i]= new int[n];
 8         }
 9         delete[]p;
10         p=NULL;