What are pointers in C++?

Programming Language
#1

Pointer in C++ language is a variable, it is also known as locator or indicator that points to an address of a value.

Advantages of Pointer:-

  • Pointer improves the performance.
  • We can return multiple values from function using pointer.
  • It makes you able to access any memory location in the computer’s memory.

& (ampersand sign) - The address operator is used to determine the address of a variable.

∗ (asterisk sign) - Indirection operator is used to access the value of an address.

int main()  
{  
int number=30;    
int ∗p;      
p=&number;    
cout<<"Address of number variable is:"<<&number<<endl;    
cout<<"Address of p variable is:"<<p<<endl;    
cout<<"Value of p variable is:"<<*p<<endl;    
   return 0;  
}

Sizeof() is an operator that evaluates the size of data type, constants, variable

  std::cout << "Size of integer data type : " <<sizeof(int)<< std::endl;  
  std::cout << "Size of float data type : " <<sizeof(float)<< std::endl;

A void pointer is a general-purpose pointer that can hold the address of any data type, but it is not associated with any data type, even the address of a variable to the variable of a different data type.

 void *ptr; // void pointer declaration  
  int *ptr1; // integer pointer declaration  
  int data=10; // integer variable initialization  
  ptr=&data;  // storing the address of data variable in void pointer variable  
  ptr1=(int *)ptr; // assigning void pointer to integer pointer  
  std::cout << "The value of *ptr1 is : " <<*ptr1<< std::endl;  
  return 0;