Dynamic Memory Allocation in C++: (new operator)

In C++ we can allocate static memory or Dynamic memory to the variables as well as objects in C++

Dynamic memory allocation is also known as free store memory allocation or heap memory allocation

We can allocate dynamic memory or memory at run time by using new operator in C++

//dynamic memory allocation in CPP
#include<iostream>
using namespace std;
int main()
{
int *ptr;
ptr=new int;//new is used to allocation dynamic memory
*ptr=10;
cout<<*ptr;

}//end of main

//Dynamic memory allocation in C++ to integer array.
#include<iostream>
using namespace std;
int main()
{
int *ptr;
int i;
ptr=new int[5];//dynamic memory allocation

for(i=0;i<5;i++)
{
cout<<endl<<"Enter a value: ";
cin>>*(ptr+i);
}//end of loop
cout<<endl<<"Values of the array are: "<<endl;
for(i=0;i<5;i++)
{
cout<<*(ptr+i)<<" ";
}
return 0;
}//end of main

//Dynamic memory allocation in C++ to Structure
#include<iostream>
using namespace std;
struct student
{
char name[10];
int rollno;
float fee;
};
int main()
{
student *sptr;
sptr=new student;
cout<<"Enter the name of the student: ";
cin>>sptr->name;
cout<<"Enter the rollno of the student: ";
cin>>sptr->rollno;
cout<<"Enter the fee of the student: ";
cin>>sptr->fee;

cout<<endl<<"values of the structure are: "<<endl;
cout<<"Name is : "<<sptr->name<<endl;
cout<<"Rollno is : "<<sptr->rollno<<endl;
cout<<"Fee is : "<<sptr->fee<<endl;

return 0;
}//end of main

//Dynamic memory allocation to object
#include<iostream>
using namespace std;
class Demo
{
public:
int ctr;

Demo()//default constructor
{
ctr=0;

}
void setData(int n1)
{
ctr=n1;

}
void showData()
{
cout<<endl<<"ctr="<<ctr;
}

};//end of class

int main()
{
Demo *dptr;//creating pointer of Demo class
dptr=new Demo;//allocating memory on free store
dptr->setData(100);
dptr->showData();
delete dptr;//deallocating memory from free store
} //end of main