第八周-运算符重载-分数类中的运算符重载-四则运算

<pre class="cpp" name="code">/* * Copyright (c) 2014, 烟台大学计算机学院 * All rights reserved. * 文件名称：test.cpp * 作    者：刘畅 * 完成日期：2015 年 4  月  25  日 * 版 本 号：v1.0 * * 问题描述：在（1）的基础上，实现分数类中的对象和整型数的四则运算。分数类中的对象可以和整型数进行四则运算，且运算符合交换律。例如：CFraction a(1,3),b; int i=2; 可以完成b=a+i;。同样，可以完成i+a, 45+a, a*27, 5/a等各种运算。　* 输入描述： ；* 程序输出： 按要求输出。

 

#include <iostream>#include <cmath>using namespace std;int gcd(int x, int y);class CFraction{private:    int nume;  // 分子    int deno;  // 分母public:    CFraction(int nu=0,int de=1):nume(nu),deno(de) {}    void simplify();    void display();    friend CFraction operator+(const CFraction &c1, const CFraction &c2);  //两个分数相加，结果要化简    friend CFraction operator-(const CFraction &c1, const CFraction &c2);  //两个分数相减，结果要化简    friend CFraction operator*(const CFraction &c1, const CFraction &c2);  //两个分数相乘，结果要化简    friend CFraction operator/(const CFraction &c1, const CFraction &c2);  //两个分数相除，结果要化简    friend CFraction operator+(const CFraction &c, int i);    friend CFraction operator+(int i, const CFraction &c );    friend CFraction operator-(const CFraction &c, int i);    friend CFraction operator-(int i, const CFraction &c );    friend CFraction operator*(const CFraction &c, int i);    friend CFraction operator*(int i, const CFraction &c );    friend CFraction operator/(const CFraction &c, int i);    friend CFraction operator/(int i, const CFraction &c );    CFraction operator+();  //取正一目运算    CFraction operator-();  //取反一目运算    friend bool operator>(const CFraction &c1, const CFraction &c2);    friend bool operator<(const CFraction &c1, const CFraction &c2);    friend bool operator==(const CFraction &c1, const CFraction &c2);    friend bool operator!=(const CFraction &c1, const CFraction &c2);    friend bool operator>=(const CFraction &c1, const CFraction &c2);    friend bool operator<=(const CFraction &c1, const CFraction &c2);    friend bool operator>(const CFraction &c, int i);    friend bool operator>(int i, const CFraction &c);    friend bool operator<(const CFraction &c, int i);    friend bool operator<(int i, const CFraction &c);    friend bool operator==(const CFraction &c, int i);    friend bool operator==(int i, const CFraction &c);    friend bool operator!=(const CFraction &c, int i);    friend bool operator!=(int i, const CFraction &c);    friend bool operator>=(const CFraction &c, int i);    friend bool operator>=(int i, const CFraction &c);    friend bool operator<=(const CFraction &c, int i);    friend bool operator<=(int i, const CFraction &c);};void CFraction::simplify(){    int n=gcd(nume,deno);    nume/=n;    deno/=n;}int gcd(int x, int y){    int z;    while (y!=0)    {        z=x;        x=y;        y=z%y;    }    return x;}void CFraction::display(){    cout<<"("<<nume<<"/"<<deno<<")"<<endl;}CFraction operator+(const CFraction &c1, const CFraction &c2){    CFraction t;    t.nume=c1.nume*c2.deno+c2.nume*c1.deno;    t.deno=c1.deno*c2.deno;    t.simplify();    return t;}CFraction operator-(const CFraction &c1, const CFraction &c2){    CFraction t;    t.nume=c1.nume*c2.deno-c2.nume*c1.deno;    t.deno=c1.deno*c2.deno;    t.simplify();    return t;}CFraction operator*(const CFraction &c1, const CFraction &c2){    CFraction t;    t.nume=c1.nume*c2.nume;    t.deno=c1.deno*c2.deno;    t.simplify();    return t;}CFraction operator/(const CFraction &c1, const CFraction &c2){    CFraction t;    if (!c2.nume) return c1;    t.nume=c1.nume*c2.deno;    t.deno=c1.deno*c2.nume;    t.simplify();    return t;}CFraction operator+(const CFraction &c, int i){    CFraction c1(c.nume+i*c.deno,c.deno);    c1.simplify();    return c1;}CFraction operator+(int i, const CFraction &c ){    CFraction c1(c.nume+i*c.deno,c.deno);    c1.simplify();    return c1;}CFraction operator-(const CFraction &c, int i){    CFraction c1(c.nume-i*c.deno,c.deno);    c1.simplify();    return c1;}CFraction operator-(int i, const CFraction &c ){    CFraction c1(i*c.deno-c.nume,c.deno);    c1.simplify();    return c1;}CFraction operator*(const CFraction &c, int i){    CFraction c1(c.nume*i,c.deno);    c1.simplify();    return c1;}CFraction operator*(int i, const CFraction &c ){    CFraction c1(c.nume*i,c.deno);    c1.simplify();    return c1;}CFraction operator/(const CFraction &c, int i){    CFraction c1(c.nume,c.deno*i);    c1.simplify();    return c1;}CFraction operator/(int i, const CFraction &c ){    CFraction c1(i*c.deno,c.nume);    c1.simplify();    return c1;}CFraction CFraction:: operator+(){    CFraction c;    c.nume=nume;    c.deno=deno;    c.simplify();    return c;}CFraction CFraction:: operator-(){    CFraction c;    c.nume=-nume;    c.deno=-deno;    c.simplify();    return c;}bool operator>(const CFraction &c1, const CFraction &c2){    int c1_nume,c2_nume,common_deno;    c1_nume=c1.nume*c2.deno;    c2_nume=c2.nume*c1.deno;    common_deno=c1.deno*c2.deno;    if((c1_nume-c2_nume)*common_deno>0)        return true;    return false;}bool operator<(const CFraction &c1, const CFraction &c2){    int c1_nume,c2_nume,common_deno;    c1_nume=c1.nume*c2.deno;    c2_nume=c2.nume*c1.deno;    common_deno=c1.deno*c2.deno;    if ((c1_nume-c2_nume)*common_deno<0)        return true;    return false;}bool operator==(const CFraction &c1, const CFraction &c2){    if (c1!=c2) return false;    return true;}bool operator!=(const CFraction &c1, const CFraction &c2){    if (c1>c2 || c1<c2) return true;    return false;}bool operator>=(const CFraction &c1, const CFraction &c2){    if (c1<c2) return false;    return true;}bool operator<=(const CFraction &c1, const CFraction &c2){    if (c1>c2) return false;    return true;}bool operator>(const CFraction &c, int i){    if(c.deno>0)        return c.nume>(i*c.deno);    else        return c.nume<(i*c.deno);}bool operator>(int i, const CFraction &c){    if(c.deno>0)        return (i*c.deno)>c.nume;    else        return (i*c.deno)<c.nume;}bool operator<(const CFraction &c, int i){    if(c.deno>0)        return c.nume<(i*c.deno);    else        return c.nume>(i*c.deno);}bool operator<(int i, const CFraction &c){    if(c.deno>0)        return (i*c.deno)<c.nume;    else        return (i*c.deno)>c.nume;}bool operator==(const CFraction &c, int i){    return c.nume==(i*c.deno);}bool operator==(int i, const CFraction &c){    return c.nume==(i*c.deno);}bool operator!=(const CFraction &c, int i){    return c.nume!=(i*c.deno);}bool operator!=(int i, const CFraction &c){    return c.nume!=(i*c.deno);}bool operator>=(const CFraction &c, int i){    return !(c<i);}bool operator>=(int i, const CFraction &c){    return !(i<c);}bool operator<=(const CFraction &c, int i){    return !(c>i);}bool operator<=(int i, const CFraction &c){    return !(i>c);}int main(){    CFraction x(1,3),y(-5,10),s;    cout<<"分数x=1/3      y=-5/10"<<endl;    s=+x+y;    cout<<"+x+y=";    s.display();    s=x-y;    cout<<"x-y=";    s.display();    s=x*y;    cout<<"x*y=";    s.display();    s=x/y;    cout<<"x/y=";    s.display();    s=-x+y;    cout<<"-x+y=";    s.display();    x.display();    if (x>y) cout<<"大于"<<endl;    if (x<y) cout<<"小于"<<endl;    if (x==y) cout<<"等于"<<endl;    y.display();    cout<<endl;    CFraction c1(5,3),c2;    c2=c1+5;    c2.display();    c2=5+c1;    c2.display();    c2=c1-5;    c2.display();    c2=5-c1;    c2.display();    c2=c1*5;    c2.display();    c2=5*c1;    c2.display();    c2=c1/5;    c2.display();    c2=5/c1;    c2.display();    bool b;    b=(c1>2);    cout<<b<<endl;    b=(2>c1);    cout<<b<<endl;    return 0;}

运行结果：

学习心得：

看得头晕眼花，写到最后还是错了。。。然后选择了复制贺老师的代码。。。有所改动，也有所欠缺，并没有用单步去观察