《Accelerated C++》学生成绩制表输出程序源码

最近在看《Accelarate C++》这本书，然后抛开书本自己码一遍书上的程序，如果你也准备看这本书，希望可以对你有点帮助，以上。

c文件和h文件、程序包含头文件的定义

主程序 main.c

#include <iostream.h>
#include <ios>
#include <vector.h>
#include <iomanip.h>
#include <string.h>
#include <algorithm>
#include <stdexcept>
#include "grade.h"
#include "Student_info.h"

using std::cin;				using std::cout;
using std::string;			using std::vector;
using std::endl;			using std::sort;
using std::domain_error;	using std::max;
using std::setprecision;	using std::streamsize;

int main(){
	vector<Student_info> students;
	Student_info record;
	string::size_type maxlen = 0;
	
	//读入数据
	while(read(cin, record)){
		maxlen = max(maxlen, record.name.size());
		students.push_back(record);
	} 
	//按字母顺序排列学生成绩记录
	sort(students.begin(), students.end(), compare); 
	//输出
	for(vector<Student_info>::size_type i = 0; i!=students.size(); ++i){
		cout<<students[i].name<<string(maxlen+1-students[i].name.size(), ' ');
		try{
 			double final_grade = grade(students[i]);
 			streamsize prec = cout.precision();
 			cout<<setprecision(3)<<final_grade<<setprecision(prec); 
		}catch (domain_error e){
			cout<<e.what();
		}
		cout<<endl;
	} 
	return 0;
}

计算中值函数： median.cpp

#include <algorithm>
#include <stdexcept>
#include <vector.h>


using std::domain_error;
using std::sort;
using std::vector;


double median(vector<double> vec){
	typedef vector<double>::size_type vec_sz;
	vec_sz size = vec.size();
	if(size == 0)
	throw domain_error("median of an empty vector");
	
	sort(vec.begin(),vec.end());
	vec_sz mid = size/2;
	return size%2 == 0 ?  (vec[mid] + vec[mid-1])/2 : vec[mid];
}

读数据函数 read.cpp

#include "Student_info.h"

using std::istream; 	using std::vector;
using std::cout;		using std::endl; 	
bool compare(const Student_info& x, const Student_info& y){
	return x.name < y.name;
}

istream& read(istream& is, Student_info& s){
//	cout<<"please enter name/midterm grade/finalterm grade: "<<endl;
	is >>s.name >>s.midterm>>s.final;
//	cout<<"please enter homework grades: "<<endl;
	read_hw(is, s.homework);
	return is;
}

istream& read_hw(istream& is, vector<double>& hw){
	if(is){
		hw.clear();
		double x;
		while(is>>x)
		hw.push_back(x);
		//清楚流以使输入动作对下一个学生有效
		is.clear(); 
	}
	return is;
}

几个计算成绩函数的grade函数（重载：函数名相同，传参不同）

#include <vector.h>
#include <stdexcept>
#include "grade.h"
#include "median.h"
#include "Student_info.h"

using std::domain_error;  using std::vector;




double grade(double midterm, double final, double homework){
	return midterm*0.2 + final*0.4 + homework*0.4;
} 

double grade(double midterm, double final, const vector<double>& hw){
	if(hw.size() == 0){
		throw domain_error("student has done no homework");
	}
	return grade(midterm, final, median(hw));
}

double grade(const Student_info& s){
	return grade(s.midterm, s.final, s.homework);
}

median.h

#ifndef GUARD_median_h
#define GUARD_median_h
#include <vector.h>
double median(std::vector<double>);
#endif

定义students_info结构体，声明读数据read（）函数

#ifndef GUARD_Student_info
#define GUARD_Student_info

#include <iostream.h>
#include <string.h>
#include <vector.h>

//结构体的定义 
struct Student_info{
	std::string name;
	double midterm,final;
	std::vector<double> homework;
};

bool compare (const Student_info&,const Student_info&);
std::istream& read(std::istream&, Student_info&); 
std::istream& read_hw(std::istream&, std::vector<double>&);

#endif

声明计算成绩的三个函数 grade（）

#ifndef GUARD_grade_h
#define GUARD_grade_h


#include <vector.h>
#include "Student_info.h"
double grade(double, double, double);
double grade(double, double, const std::vector<double>&);
double grade(const Student_info&);
#endif

以上是本书中第一个比较大的程序的所有内容，仅供参考。

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《Accelerated C++》学生成绩制表输出程序源码

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