c61.cpp

《C++程序设计习题及解答》配套代码VC版

// c61.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <iostream.h>
#include <strstrea.h>

const int SIZE = 9;

// --------------------------------------------------------------------------
class Plot
{
	friend ostream& operator<<( ostream& stream, Plot o );

public:
	Plot( int i, int j )
	{
		if ( i > SIZE ) i = SIZE;
		if ( i < 0 ) i = 0;
		if ( j > SIZE ) j = SIZE;
		if ( j < 0 ) j = 0;
		x = i;
		y = j;
	}

private:
	int x, y;
};

// --------------------------------------------------------------------------
ostream& operator<<( ostream& stream, Plot o )
{
	for ( int j = SIZE; j >= 0; j-- )
	{
		stream << j;
		if ( j == o.y )
		{
			for ( int i = 0; i < 2 * o.x - 1; i++ ) 
				stream << " ";
			stream << '*';
		}

		if ( j == 0 )
			break;

		stream << endl;
	}

	for ( int i = 1; i <= SIZE; i++ )
		stream << " " << i;
	stream << endl;

	return stream;
}

// --------------------------------------------------------------------------
int main(int argc, char* argv[])
{
	Plot a(2, 3), b(6, 4);

	// ------------------------------------
	cout << "Output using cout:\n";
	cout << a << endl << b << endl;

	// ------------------------------------
	char str[200];
	ostrstream outs( str, sizeof(str) );

	outs << a << endl << b << endl;
	outs << '\0';
	cout << "Output using in - RAM formatting:\n";
	cout << str;

	return 0;
}