From 33613a85afc4b1481367fbe92a17ee59c240250b Mon Sep 17 00:00:00 2001 From: Sven Eisenhauer Date: Fri, 10 Nov 2023 15:11:48 +0100 Subject: add new repo --- Bachelor/Prog1/examples/ch03/Fig03_12.cpp | 96 +++++++++++++++++++++++++++++++ 1 file changed, 96 insertions(+) create mode 100644 Bachelor/Prog1/examples/ch03/Fig03_12.cpp (limited to 'Bachelor/Prog1/examples/ch03/Fig03_12.cpp') diff --git a/Bachelor/Prog1/examples/ch03/Fig03_12.cpp b/Bachelor/Prog1/examples/ch03/Fig03_12.cpp new file mode 100644 index 0000000..593c27a --- /dev/null +++ b/Bachelor/Prog1/examples/ch03/Fig03_12.cpp @@ -0,0 +1,96 @@ +// Fig. 3.12: fig03_12.cpp +// A scoping example. +#include + +using std::cout; +using std::endl; + +void useLocal( void ); // function prototype +void useStaticLocal( void ); // function prototype +void useGlobal( void ); // function prototype + +int x = 1; // global variable + +int main() +{ + int x = 5; // local variable to main + + cout << "local x in main's outer scope is " << x << endl; + + { // start new scope + + int x = 7; + + cout << "local x in main's inner scope is " << x << endl; + + } // end new scope + + cout << "local x in main's outer scope is " << x << endl; + + useLocal(); // useLocal has local x + useStaticLocal(); // useStaticLocal has static local x + useGlobal(); // useGlobal uses global x + useLocal(); // useLocal reinitializes its local x + useStaticLocal(); // static local x retains its prior value + useGlobal(); // global x also retains its value + + cout << "\nlocal x in main is " << x << endl; + + return 0; // indicates successful termination + +} // end main + +// useLocal reinitializes local variable x during each call +void useLocal( void ) +{ + int x = 25; // initialized each time useLocal is called + + cout << endl << "local x is " << x + << " on entering useLocal" << endl; + ++x; + cout << "local x is " << x + << " on exiting useLocal" << endl; + +} // end function useLocal + +// useStaticLocal initializes static local variable x only the +// first time the function is called; value of x is saved +// between calls to this function +void useStaticLocal( void ) +{ + // initialized first time useStaticLocal is called. + static int x = 50; + + cout << endl << "local static x is " << x + << " on entering useStaticLocal" << endl; + ++x; + cout << "local static x is " << x + << " on exiting useStaticLocal" << endl; + +} // end function useStaticLocal + +// useGlobal modifies global variable x during each call +void useGlobal( void ) +{ + cout << endl << "global x is " << x + << " on entering useGlobal" << endl; + x *= 10; + cout << "global x is " << x + << " on exiting useGlobal" << endl; + +} // end function useGlobal + +/************************************************************************** + * (C) Copyright 1992-2003 by Deitel & Associates, Inc. and Prentice * + * Hall. 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. * + *************************************************************************/ -- cgit v1.2.3