why should i use pointers in c++ code example

Example 1: c++ pointers

#include <iostream>

using namespace std;

int main () {
   int  var = 20;   // actual variable declaration.
   int  *ip;        // pointer variable 

   ip = &var;       // store address of var in pointer variable

   cout << "Value of var variable: "; 
   cout << var << endl; //Prints "20"

   // print the address stored in ip pointer variable
   cout << "Address stored in ip variable: ";
   cout << ip << endl; //Prints "b7f8yufs78fds"

   // access the value at the address available in pointer
   cout << "Value of *ip variable: ";
   cout << *ip << endl; //Prints "20"

   return 0;
}

Example 2: Function pointer C++

void one() { cout << "One\n"; }
void two() { cout << "Two\n"; }


int main()
{
	void (*fptr)(); //Declare a function pointer to voids with no params

	fptr = &one; //fptr -> one
	*fptr(); //=> one()

	fptr = &two; //fptr -> two
	*fptr(); //=> two()

	return 0;
}