BJFU2023-C++程序设计-实验4-运算符重载_cout << (c1 != c2) << endl;报错

Singer类

描述

实现一个Singer类，通过以下测试：

int main()

{

Singer s1,s2;

cin>>s1>>s2;

cout<<s1<<"\n"<<s2<<endl;

if(s1>s2)

cout<<s1.getName()<<"'s score is higher than "<<s2.getName()<<"'s.\n";

else if(s1==s2)

cout<<s1.getName()<<"'s score is equal to "<<s2.getName()<<"'s.\n";

else

cout<<s1.getName()<<"'s score is lower than "<<s2.getName()<<"'s.\n";

return 0;

}

输入

输入包含两行，第一行为歌手s1的信息，第二行为歌手s2的信息，每位歌手的信息包括姓名（不包含空格）、性别、年龄 和 分数；姓名、性别、年龄和分数之间用空格分隔

输出

输出为三行，前两行分别是歌手s1和s2的信息，第三行根据s1和s2比较结果输出（s1和s2的比较结果和他们的分数的比较结果一致），具体参见主函数

输入样例 1 

Mary F 28 99.5
Peter M 26 98

输出样例 1

Mary F 28 99.5
Peter M 26 98
Mary's score is higher than Peter's.

提示

后台已有main函数，提交时去掉main函数

// 注意：无需提交main函数
#include<iostream>
using namespace std;
 
class Singer {
public:
	string m_name;
	char m_sex;
	int m_age;
	double m_score;
public:
	string getName();
	friend istream& operator>>(istream& in, Singer &s);
	friend ostream& operator<<(ostream& out, const Singer &s);
	friend bool operator>(const Singer s1, const Singer s2);
	friend bool operator==(const Singer s1, const Singer s2);
};
bool operator>(const Singer s1, const Singer s2) {
	if (s1.m_score > s2.m_score)
		return true;
	else
		return false;
}
 
bool operator==(const Singer s1, const Singer s2) {
	if (s1.m_score == s2.m_score)
		return true;
	else
		return false;
}
 
istream& operator>>(istream& in, Singer &s) {
	in >> s.m_name >> s.m_sex >> s.m_age >> s.m_score;
	return in;
}
 
ostream& operator<<(ostream& out, const Singer &s) {
	out << s.m_name <<" " << s.m_sex <<" "<<s.m_age << " " << s.m_score ;
	return out;
}
 
string Singer::getName() {
	return m_name;
}

Sales_data类

描述

实现以下Sales_data类（包括它的友元函数）：

class Sales_data {

//依次输入书号、销量和收入

friend istream & operator>>(istream&, Sales_data &);

//依次输出书号、销量、收入和均价

friend ostream & operator<<(ostream &, const Sales_data &);

// 判两个对象==的条件是它们的3个属性（书号、销量和收入）都一样

friend bool operator==(const Sales_data &, const Sales_data &);

friend bool operator!=(const Sales_data &, const Sales_data &);

// for "+", assume that both objects refer to the same book

friend Sales_data operator+(const Sales_data &, const Sales_data &);

public:

Sales_data(): units_sold(0), revenue(0.0) {}

Sales_data(const string & s, unsigned n, double r): bookNo(s), units_sold(n), revenue(r) {}

string get_bookNo() const;

// for "+=", assume that both objects refer to the same book

Sales_data & operator+=(const Sales_data &);

private:

double avg_price() const; //均价，等于收入除以销量

string bookNo; //书号

unsigned units_sold; //销量

double revenue; //收入

};

通过以下main函数的测试

int main(){

Sales_data item1,item2;

while(cin>>item1>>item2){

cout<<item1<<"\n"<<item2<<"\n";

if(item1==item2)

cout<<item1.get_bookNo()<<" equals "<<item2.get_bookNo()<<"\n";

if(item1!=item2)

cout<<item1.get_bookNo()<<" doesn't equal "<<item2.get_bookNo()<<"\n";

cout<<(item1+item2)<<"\n";

item1 += item2;

cout<<item1<<"\n";

}

return 0;

}

输入

输入多组数据，每组数据两行，每行表示1个Sales_data对象，依次是书号、销量和收入

输出

对于每组数据，输出5行，具体参见main函数和输出样例

输入样例 1 

001 10 100.0
001 10 100.0

输出样例 1

001 10 100 10
001 10 100 10
001 equals 001
001 20 200 10
001 20 200 10

输入样例 2 

002 5 250
003 8 400

输出样例 2

002 5 250 50
003 8 400 50
002 doesn't equal 003
002 13 650 50
002 13 650 50

提示

后台已有main函数，提交时去掉main函数

// 注意：无需提交main函数
#include<iostream>
using namespace std;
 
class Sales_data {
	friend istream& operator>>(istream&, Sales_data&);
	friend ostream& operator<<(ostream&, const Sales_data&);
	friend bool operato