hour09_1.cpp

《24学时精通c++》的随书源码的下半部分。欢迎下载学习。

 // Listing 9.2 Using pointers
 #include <iostream>
 using std::cout; // this file uses std::cout

 int main()
 {
     int myAge;         // a variable
     int * pAge = 0;    // a pointer   -- set to zero instead of NULL

     myAge = 5;
     pAge = &myAge;     // assign address of myAge to pAge
     cout << "myAge: " << myAge << "\n";
     cout << "*pAge: " << *pAge << "\n\n";

     cout << "*pAge = 7\n";
     *pAge = 7;         // sets myAge to 7
     cout << "*pAge: " << *pAge << "\n";
     cout << "myAge: " << myAge << "\n\n";

     cout << "myAge = 9\n";
     myAge = 9;
     cout << "myAge: " << myAge << "\n";
     cout << "*pAge: " << *pAge << "\n";

// The results are usually the same with the pointer initialized to 0 or NULL.
// It is just a good practice to use the word NULL because it is more obvious!

     return 0;
 }