polymult.cpp

C++&datastructure书籍源码,以前外教提供现在与大家共享

#include <iostream>
using namespace std;

#include "poly.h"

Poly MonoMult(const Poly& mono, const Poly& rhs)
// pre: mono is a single term (monomial)
// post: return mono*rhs
//       if mono is a polynomial, returns mono.Head()*rhs
{
    if (rhs.IsPoly())
    {   return Poly(mono.leadingCoeff()*rhs.leadingCoeff(),
                    mono.degree() + rhs.degree()) + MonoMult(mono,rhs.Tail());
    }
    return Poly::ZERO;  // base case accumulated properly
}

int main()
{
    Poly p1,p2,p3,p4;
    double x;
    cout << "value of x ";
    cin >> x;
    
    p1 = Poly(3,2) + Poly(4,1) + Poly(-3,0);
    p2 = Poly(4,2) + Poly(3,1) + Poly(2,0);
    p3 = Poly(5,3);
    
    cout << "p1 at " << x << ", " << p1.at(x) << "\t : " << p1 << endl;
    cout << "p2 at " << x << ", " << p2.at(x) << "\t : " << p2<< endl;
    cout << "p3 at " << x << ", " << p3.at(x) << "\t : " << p3 << endl;
    p4 = MonoMult(p3,p1);
    cout << "p4 at " << x << ", " << p4.at(x) << "\t : " << p4 << endl; 
    cout << "5p4 at " << x << ", " << (5*p4).at(x) << "\t : " << 5*p4 << endl;
    
    cout << "total # terms used = " << Poly::TermsAllocated() << endl;
    return 0;
}