### Pointers

I'm trying to get the addresses of d2 and d3, and I know I am off. Then I want to point to the pointers. Any suggestions?

 ``12345678910111213141516171819202122232425262728293031323334`` `````` 1 #include 2 3 using namespace std; 4 5 int main() 6 { 7 double d1 = 7.8; 8 double d2 = 10.0; 9 double d3 = 0.009; 10 11 double* d; 12 d = &d1; 13 d = &d2; 14 d = &d3; 15 16 double **dp; 17 dp = &d1; 18 dp = &d2; 19 dp = &d3; 20 21 cout << "d1 = " << d1 << endl; 22 cout << "*d = " << d << endl; 23 cout << "dp = " << *(*dp) << endl; 24 25 cout << "d2 = " << d2 << endl; 26 cout << "*d = " << d << endl; 27 cout << "dp = " << *(*dp) << endl; 28 29 cout << "d3 = " << d3 << endl; 30 cout << "*d = " << d << endl; 31 cout << "dp = " << *(*dp) << endl; 32 33 return 0; 34 }``````
A pointer can only point to one thing at a time. If you look at, say, line 11-14, you declare only one pointer, then assign it the address of three different variables. In the end, it only holds the address of the third. Second, line 16 is specifically a pointer to a pointer. You can't make it hold the address of something that is not actually a pointer as well. In other words, a double-pointer only points to pointers, while pointers can point to... well, anything, really. But they can only point to one thing at a time.
I dont know what are you trying to achieve ,But I think this code will help you so much

 ``12345678910111213141516171819202122232425262728293031`` ``````# include using namespace std; int main() { double d1 = 7.8; double d2 = 10.0; double d3 = 0.009; double *ptr1,*ptr2,*ptr3; ptr1 = &d1; ptr2 = &d2; ptr3 = &d3; cout << "The value of d1 is : " << d1 << endl; cout << "Or at this way " << *ptr1 << endl; cout << "The address of d1 is : " << &d1 << endl; cout << "Or at this way " << ptr1 << endl; /// Same thing for the other varaibles double **dp; dp = &ptr1; cout << "The value of d1 is : " << **dp << endl; cout << "The address of d1 is : " << *dp << endl; cout << "The address of dp is : " << dp << endl; return 0; }``````

Hope that helps
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