root.cpp

来自「钱能的《C++程序设计习题及解答》配套代码」· C++ 代码 · 共 72 行

// Root.cpp: implementation of the Root class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "Root.h"

#include <iostream.h>
#include <iomanip.h>
#include <math.h>
#include "Real.h"

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

Root::Root( double m1, double m2, double m3 )
:
a(m1), b(m2), c(m3)
{

}

Root::~Root()
{

}

void Root::Print()
{
	cout << "方程";
	cout << a;
	cout << setiosflags( ios::showpos );
	cout << "*X*X";
	cout << b << "*X";
	cout << c << " = 0\n";
	cout << resetiosflags( ios::showpos );
}

void Root::Solve()
{
	Print();
	cout << "的解是：\n";

	double delta = b * b - 4 * a * c;
	if ( fabs(delta) < 1e-5 )
	{
		Real x( -b/2/a );
		cout << "\nX1=X2=";
		x.Print();
	}
	else if ( delta > 0 )
	{
		Real x1( -b/2/a + sqrt(delta)/2/a );
		Real x2( -b/2/a - sqrt(delta)/2/a );
		cout << "\nX1 = ";
		x1.Print();
		cout << "\nX2 = ";
		x2.Print();
	}
	else
	{
		Complex x1( -b/2/a, sqrt(-delta)/2/a );
		Complex x2( -b/2/a, -sqrt(-delta)/2/a );
		cout << "\nX1 = ";
		x1.Print();
		cout << "\nX2 = ";
		x2.Print();
	}

}