pointer to constant
#include<iostream>
int main()
{
int number_1{100};
int number_2 {200};
//the data(value) pointed by the pointer is constant
const int *some_ptr {&number_1};
*some_ptr = 300 ; //Error
*some_ptr = &number_2 ; // ok => the aderss is different
//the adress pointed by the pointer is constant
int *const some_ptr {&number_1} ;
some_ptr = &number_2 //error => the adress of the pointer is constant
*some_ptr = 123 // ok
// the adress and the data is constant
const int const *some_ptr{&number_1};
*some_ptr = 32; // error
some_ptr = &number_2; // error
return 0;
}