嚴蔚敏2.39

//用鏈表求多項式的值
#include <iostream>
#include <time.h>
using namespace std;

class Factor
{
public:
	float coeff;
	int Exp;
};

class PolyTerm
{
public:
	int Length;
	Factor *fac;
	void Create_PolyTerm();
	int GetValue(float x);
	void Show_PolyTerm();
};

void PolyTerm::Create_PolyTerm()
{
	srand(time(NULL));
	Length=int(rand()%12);
	float Max,Min;
	fac=new Factor[Length+1];
	for (int i=0;i<=Length;i++)
	{
		Max=float(rand()%640);
		Min=float(1.0+rand()%480);
		fac[i].coeff=Max/Min;
		fac[i].Exp=i;
	}
}

void PolyTerm::Show_PolyTerm()
{
	int i;
	cout<<"多項式爲："<<endl;
	cout<<fac[0].coeff<<"*X^0";
	for (i=1;i<=Length;i++)
	{
		cout<<"+"<<fac[i].coeff<<"*X^"<<fac[i].Exp;
	}
	cout<<endl;
}

int PolyTerm::GetValue(float x)
{
	float sum,sum_x;
	int Exp,i;
	sum=0.0;
	sum_x=1.0;
	Exp=0;
	i=1;
	while(i<=Length)
	{
		Exp=1;
		sum_x=1.0;
		while(Exp<=fac[i].Exp)
		{
			sum_x*=x;
			Exp+=1;
		}
		sum+=sum_x*fac[i].coeff;
		i+=1;
	}
	sum+=fac[0].coeff;
	cout<<"總和爲："<<sum<<endl;
	return 1;
}

int main()
{
	PolyTerm by;
	float x;
	by.Create_PolyTerm();
	by.Show_PolyTerm();
	cout<<"請輸入X的值:";
	cin>>x;
	if (by.GetValue(x))
		return 1;
	else
	{
		cout<<"求和失敗！"<<endl;
		return 0;
	}
}