fig18_04.cpp

经典的<<C how to program>一书第三版的例程。非常适合于C的初学者。

// Fig. 18.4: fig18_04.cpp
// Driver for simple class Array
#include <iostream>

using std::cout;
using std::cin;
using std::endl;

#include "array1.h"

int main()
{
   // no objects yet
   cout << "# of arrays instantiated = "
        << Array::getArrayCount() << '\n';

   // create two arrays and print Array count
   Array integers1( 7 ), integers2;
   cout << "# of arrays instantiated = "
        << Array::getArrayCount() << "\n\n";

   // print integers1 size and contents
   cout << "Size of array integers1 is "
        << integers1.getSize()
        << "\nArray after initialization:\n"
        << integers1 << '\n';

   // print integers2 size and contents
   cout << "Size of array integers2 is "
        << integers2.getSize()
        << "\nArray after initialization:\n"
        << integers2 << '\n';

   // input and print integers1 and integers2
   cout << "Input 17 integers:\n";
   cin >> integers1 >> integers2;
   cout << "After input, the arrays contain:\n"
        << "integers1:\n" << integers1
        << "integers2:\n" << integers2 << '\n';

   // use overloaded inequality (!=) operator
   cout << "Evaluating: integers1 != integers2\n";
   if ( integers1 != integers2 )
      cout << "They are not equal\n";

   // create array integers3 using integers1 as an
   // initializer; print size and contents
   Array integers3( integers1 );

   cout << "\nSize of array integers3 is "
        << integers3.getSize()
        << "\nArray after initialization:\n"
        << integers3 << '\n';

   // use overloaded assignment (=) operator
   cout << "Assigning integers2 to integers1:\n";
   integers1 = integers2;
   cout << "integers1:\n" << integers1
        << "integers2:\n" << integers2 << '\n';

   // use overloaded equality (==) operator
   cout << "Evaluating: integers1 == integers2\n";
   if ( integers1 == integers2 )
      cout << "They are equal\n\n";

   // use overloaded subscript operator to create rvalue
   cout << "integers1[5] is " << integers1[ 5 ] << '\n';

   // use overloaded subscript operator to create lvalue
   cout << "Assigning 1000 to integers1[5]\n";
   integers1[ 5 ] = 1000;
   cout << "integers1:\n" << integers1 << '\n';

   // attempt to use out of range subscript
   cout << "Attempt to assign 1000 to integers1[15]" << endl;
   integers1[ 15 ] = 1000;  // ERROR: out of range

   return 0;
}



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 * (C) Copyright 2000 by Deitel & Associates, Inc. and Prentice Hall.     *
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