what I mean by undefined error is because I don't know what the error is about. :P, actually it's because the error not from the code itself, but it's about a compiler that can't defined some sort of file...
btw, as title said, the error is from the code in Accelerated C++ book, you can see attachment that I included to analyze the error that I had.
and here the code, [from main.cpp]
#include <algorithm>
#include <iomanip>
#include <ios>
#include <iostream>
#include <stdexcept>
#include <string>
#include <vector>
#include "grade.h"
#include "Student_info.h"
using std::cin; using std::setprecision;
using std::cout; using std::sort;
using std::domain_error; using std::streamsize;
using std::endl; using std::string;
using std::max; using std::vector;
int main()
{
vector<Student_info> students;
Student_info record;
string::size_type maxlen = 0; // the length of the longest name
// read and store all the students data.
// Invariant: students contains all the student records read so far
// maxlen contains the length of the longest name in students
while (read(cin, record)) {
// find length of longest name
maxlen = max(maxlen, record.name.size());
students.push_back(record);
}
// alphabetize the student records
sort(students.begin(), students.end(), compare);
// write the names and grades
for (vector<Student_info>::size_type i = 0;
i != students.size(); ++i) {
// write the name, padded on the right to maxlen + 1 characters
cout << students[i].name
<< string(maxlen + 1 - students[i].name.size(), ' ');
// compute and write the grade
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;
}and this one from one of the header [grade.h]
#ifndef GRADE_H_INCLUDED
#define GRADE_H_INCLUDED
// grade.h
#include <vector>
#include "Student_info.h"
double grade(double, double, double);
double grade(double, double, const std::vector<double>&);
double grade(const Student_info&);
#endif // GRADE_H_INCLUDEDthis one too [Student_info.h]
#ifndef STUDENT_INFO_H_INCLUDED
#define STUDENT_INFO_H_INCLUDED
// Student_info.h header file
#include <iostream>
#include <string>
#include <vector>
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 // STUDENT_INFO_H_INCLUDEDthat's all, thnx for reading, hope anyone bother to give a hand...
