hour05_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 5.5 - demonstrates multiple return
 // statements
 #include <iostream>

 int Doubler(int AmountToDouble);

 int main()
 {
     int result = 0;
     int input;

     std::cout << "Enter a number between 0 and "
               << "10,000 to double: ";
     std::cin >> input;

     std::cout << "\nBefore doubler is called...";
     std::cout << "\ninput: " << input
               << " doubled: " << result << "\n";

     result = Doubler(input);

     std::cout << "\nBack from Doubler...";
     std::cout << "\ninput: " << input
               << " doubled: " << result << "\n\n";

     return 0;
 }

 int Doubler(int original)
 {
     if (original <= 10000)
         return original * 2;
     else
         return -1;
     std::cout << "You can't get here!\n";
  // The line above should never execute and you may get a warning
  // about unreachable code. Comment it out and recompile, what's the message now?
  
  // You may also get a warning about not having a return at the end of the function
  // even know *we* know the the code is unreachable, the compiler may not detect that.
  // Uncomment the following line and see what happens when you compile. 

  // return 0;
  // Sometimes error and warning messages can be a little confusing!
 }