Update README.md

ch13/README.md

@@ -132,7 +132,7 @@ Yes, it does. Because, as described, the newly defined copy constructor can hand
 ## Exercise 13.16:
 >What if the parameter in f were const numbered&? Does that change the output? If so, why? What output gets generated?
 
-Yes, the output will change. Because no copy operation happens within function `f`. Thus, the three Output are the same.
+No, the output has not changed. Because the copy constructor lets a, b, and c have different mysn value. Therefore, the three Output are different.
 
 ## Exercise 13.17
 > Write versions of numbered and f corresponding to the previous three exercises and check whether you correctly predicted the output.

ch15/README.md

@@ -59,7 +59,7 @@ The static type of a pointer or reference to a base class may differ from its dy
 ## Exercise 15.10:
 > Recalling the discussion from §8.1 (p. 311), explain how the program on page 317 that passed an `ifstream` to the `Sales_data` read function works.
 
-The function takes a `std::istream` from which `std::ifstream` is derived. Hence the `ifstream` object "is a" i`stream` , which is why it works.
+The function takes a `std::istream` from which `std::ifstream` is derived. Hence the `ifstream` object "is a" `istream` , which is why it works.
 
 ## Exercise 15.11:
 > Add a virtual debug function to your `Quote` class hierarchy that displays the data members of the respective classes.