c-resources/CPlusPlus20ForProgrammers-m.../examples/ch05/fig05_08.cpp

52 lines
2.3 KiB
C++

// fig05_08.cpp
// Passing arguments by value and by reference.
#include <iostream>
using namespace std;
int squareByValue(int number); // prototype (for value pass)
void squareByReference(int& numberRef); // prototype (for reference pass)
int main() {
int x{2}; // value to square using squareByValue
int z{4}; // value to square using squareByReference
// demonstrate squareByValue
cout << "x = " << x << " before squareByValue\n";
cout << "Value returned by squareByValue: "
<< squareByValue(x) << endl;
cout << "x = " << x << " after squareByValue\n\n";
// demonstrate squareByReference
cout << "z = " << z << " before squareByReference\n";
squareByReference(z);
cout << "z = " << z << " after squareByReference\n";
}
// squareByValue multiplies number by itself, stores the
// result in number and returns the new value of number
int squareByValue(int number) {
return number *= number; // caller's argument not modified
}
// squareByReference multiplies numberRef by itself and stores the result
// in the variable to which numberRef refers in function main
void squareByReference(int& numberRef) {
numberRef *= numberRef; // caller's argument modified
}
/**************************************************************************
* (C) Copyright 1992-2022 by Deitel & Associates, Inc. and *
* Pearson Education, Inc. All Rights Reserved. *
* *
* DISCLAIMER: The authors and publisher of this book have used their *
* best efforts in preparing the book. These efforts include the *
* development, research, and testing of the theories and programs *
* to determine their effectiveness. The authors and publisher make *
* no warranty of any kind, expressed or implied, with regard to these *
* programs or to the documentation contained in these books. The authors *
* and publisher shall not be liable in any event for incidental or *
* consequential damages in connection with, or arising out of, the *
* furnishing, performance, or use of these programs. *
**************************************************************************/