C++primer plus第六版课后编程练习答案11.5和11.6

这两道题是第6题包含第5题，所以第5题我就没写了，下面是第6题的答案

头文件#ifndef STONEWt_H_#define STONEWt_H_#include<iostream>class Stonewt{private:enum{Lbs_per_stn=14};int stone;double pds_left;double pounds;int state;public:Stonewt(double lbs);Stonewt(int stn,double lbs);Stonewt();~Stonewt();void setstate();void resetStonewt(double lbs);void resetStonewt(int stn,double lbs);//void show_lbs()const;//以磅的格式显示重量//void show_stn()const;//以英石的格式显示重量operator int()const;operator double()const;Stonewt operator*(double n)const;Stonewt operator+(const Stonewt &s)const;Stonewt operator-(const Stonewt &s)const;Stonewt operator/(const Stonewt &s)const;bool operator>(const Stonewt &s)const;bool operator<(const Stonewt &s)const;bool operator>=(const Stonewt &s)const;bool operator<=(const Stonewt &s)const;bool operator==(const Stonewt &s)const;bool operator!=(const Stonewt &s)const;    friend std::ostream &operator<<(std::ostream &os,const Stonewt &s);friend std::istream &operator>>(std::istream &is,Stonewt &s);};#endif

#include<iostream>#include "stonewt.h"using namespace std;Stonewt::Stonewt(double lbs){stone=int(lbs)/Lbs_per_stn;pds_left=int(lbs)%Lbs_per_stn+lbs-(int)lbs;pounds=lbs;state=3;}Stonewt::Stonewt(int stn,double lbs){stone=stn;pds_left=lbs;pounds=stn*Lbs_per_stn+lbs;state=1;}Stonewt::Stonewt(){stone=pounds=pds_left=0;}Stonewt::~Stonewt(){}void Stonewt::setstate(){int n;cout<<"请设置对象的格式（1.英石格式,2.整数磅格式,3.浮点磅格式）";cin>>n;if(n==1)state=n;else if(n==2)state=n;else if(n==3)state=n;else{cout<<"输入错误，没有这种格式的对象";state=3;}}void Stonewt::resetStonewt(double lbs){stone=int(lbs)/Lbs_per_stn;pds_left=int(lbs)%Lbs_per_stn+lbs-(int)lbs;pounds=lbs;state=3;}void Stonewt::resetStonewt(int stn,double lbs){stone=stn;pds_left=lbs;pounds=stn*Lbs_per_stn+lbs;state=1;}/*void Stonewt::show_lbs()const{cout<<pounds<<"pounds\n";}void Stonewt::show_stn()const{cout<<stone<<" stones,"<<pds_left<<" pounds\n";}*/Stonewt::operator double()const{return (pounds);}Stonewt::operator int()const{return int (pounds+0.5);}Stonewt Stonewt::operator *(double n)const{return Stonewt(pounds*n);}Stonewt Stonewt::operator +(const Stonewt &s)const{return Stonewt(pounds+s.pounds);}Stonewt Stonewt::operator -(const Stonewt &s)const{return Stonewt(pounds-s.pounds);}Stonewt Stonewt::operator/(const Stonewt &s)const{return Stonewt(pounds/s.pounds);}std::ostream &operator<<(std::ostream &os,const Stonewt &s){if(s.state==1)os<<s.stone<<" stones,"<<s.pds_left<<" pounds\n";else if(s.state==2)os<<(int)s.pounds<<" pounds\n";else if(s.state==3)os<<s.pounds<<" pounds\n";elseos<<"输出错误，没有此种格式的对象\n";return os;}std::istream &operator>>(std::istream &is,Stonewt &s){double p;is>>p;s.resetStonewt(p);return is;}bool Stonewt::operator <(const Stonewt &s)const{if(pounds<s.pounds)return true;elsereturn false;}bool Stonewt::operator <=(const Stonewt &s)const{if(pounds<=s.pounds)return true;else return false;}bool Stonewt::operator >(const Stonewt &s)const{if(pounds>s.pounds)return true;else return false;}bool Stonewt::operator >=(const Stonewt &s)const{if(pounds>=s.pounds)return true;elsereturn false;}bool Stonewt::operator ==(const Stonewt &s)const{if(pounds==s.pounds)return true;elsereturn false;}bool Stonewt::operator !=(const Stonewt &s)const{if(pounds!=s.pounds)return true;elsereturn false;}

#include<iostream>#include "stonewt.h"using namespace std;void main(){Stonewt a(50),b(60),c(70);cout<<a+b<<endl;cout<<a-b<<endl;cout<<c/a<<endl;cout<<a*b<<endl;Stonewt n(11,0);Stonewt s[6]={10,11,12};for(int i=3;i<6;i++)cin>>s[i];Stonewt max=s[0],min=s[0];for(i=0;i<6;i++){cout<<s[i];}cout<<"大于等于11英石的元素"<<endl;for(i=0;i<6;i++){if(s[i]<min)min=s[i];if(s[i]>max)max=s[i];if(s[i]>=n)cout<<s[i];}cout<<"最大的元素"<<max;cout<<"最小的元素"<<min;}

如果想直接看第5题答案的可以到这个网址看

http://blog.csdn.net/qq844352155/article/details/24128929