C ++ confusing generic pointer

Question

I found the code below in the section "C ++ Programming Language, Fourth Edition", chapter 17.5.1.3

struct S2 { shared_ptr<int> p; }; S2 x {new int{0}}; void f() { S2 y {x}; // ''copy'' x ∗yp = 1; // change y, affects x ∗xp = 2; // change x; affects y ypreset(new int{3}); // change y; affects x ∗xp = 4; // change x; affects y } 

I don't understand the last comment, indeed, yp should point to the new memory address after calling reset (), and therefore

  ∗xp = 4; 

should leave yp unchanged, right?

thanks

Answer 1

The book is wrong and you are right. Perhaps you will send this to Bjarne so that it can be fixed in the next print. A.

Correct comments could be:

 S2 y {x}; // xp and yp point to the same int. *yp = 1; // changes the value of both *xp and *yp *xp = 2; // changes the value of both *xp and *yp ypreset(new int{3}); // xp and yp point to different ints. *xp = 4; // changes the value of only *xp