Fig01_05.cpp - Simplest IntCell class, with a test program
 
        #include <iostream.h>

        /**
         * A class for simulating an integer memory cell.
         */
        class IntCell
        {
          public:
            /**
             * Construct the IntCell.
             * Initial value is 0.
             */
            IntCell( )
              { storedValue = 0; }

            /**
             * Construct the IntCell.
             * Initial value is initialValue.
             */
            IntCell( int initialValue )
              { storedValue = initialValue; }

            /**
             * Return the stored value.
             */
            int read( )
              { return storedValue; }

            /**
             * Change the stored value to x.
             */
            void write( int x )
              { storedValue = x; }

          private:
            int storedValue;
        };

        int main( )
        {
            IntCell m;

            m.write( 5 );
            cout << "Cell contents: " << m.read( ) << endl;

            return 0;
        }