c++题目打印工资单求解

#include <iostream>
#include <iomanip>
#include <iterator>
#include <algorithm>
using namespace std;

struct foo
{
    foo() = default;

    std::string 姓名;
    double 基本工资;
    double 浮动工资;
    double 支出;
    const double 实发工资() const noexcept
    {
        return 基本工资 + 浮动工资 - 支出;
    }

    friend std::istream& operator>>( std::istream& is, foo& v )
    {
        return is >> v.姓名 >> v.基本工资 >> v.浮动工资 >> v.支出;
    }
    friend std::ostream& operator<<( std::ostream& os, const foo& v )
    {
        os << v.姓名 << ' ' << v.实发工资();
        return os;
    }
};

int main( void )
{
    foo s[3];
    copy_n( istream_iterator<foo>(cin), 3, s );

    cout << fixed << setprecision(2);
    copy_n( s, 3, ostream_iterator<foo>(cout,"\n") );
}