Hi,
Newbie here, trying to compile with g++ and getting these errors:
Undefined first referenced
symbol in file
typeinfo for Student student.o
vtable for Student student.o
ld: fatal: Symbol referencing errors. No output written to student
I've seen people posting this problem all over the web but haven't found anything that I can understand! Here's my header file:
... my definitions:Code:#include <iostream> #include <fstream> using namespace std; class Student { public: virtual void Print(ostream& os); virtual double Average(){}; Student(){}; virtual char GetSubject(){}; protected: Student(char* first, char* last, char sub); char firstName[21]; char lastName[21]; char subject; }; class English : public Student { public: English(char* first, char* last, char sub, int atten, int proj, int mid, int final); double Average(); char GetSubject(); void Print(ostream& os); private: int attendance; int project; int midterm; int finalExam; }; class History : public Student { public: History(char* first, char* last, char sub, int p, int mid, int final); double Average(); char GetSubject(); void Print(ostream& os); private: int paper; int midterm; int finalExam; }; class Math : public Student { public: Math(char* first, char* last, char sub, int q1, int q2, int q3, int q4, int q5, int t1, int t2, int final); double Average(); char GetSubject(); void Print(ostream& os); private: double quizAvg; int test1; int test2; int finalExam; };
... and just in case it matters, my main file and makefile:Code:#include <iostream> #include <cstring> #include <fstream> #include "student.h" using namespace std; Student::Student(char* first, char* last, char sub) { strcpy(firstName, first); strcpy(lastName, last); subject = sub; } English::English(char* first, char* last, char sub, int atten, int proj, int mid, int final): Student(first, last, sub) { attendance = atten; project = proj; midterm = mid; finalExam = final; } char English::GetSubject() { } void English::Print(ostream& os) { char* fullName = strcat(firstName, " "); fullName = strcat(fullName, lastName); os.width(42); os << fullName; os.width(8); os << finalExam; os.width(8); os << Average(); switch (static_cast<int>(Average()) / 10) { case 10: case 9: os << 'A'; break; case 8: os << 'B'; break; case 7: os << 'C'; break; case 6: os << 'D'; break; default: os << 'E'; } os << '\n'; } double English::Average() { return static_cast<double>(attendance + project*3 + midterm*3 + finalExam*3)/1000; } History::History(char* first, char* last, char sub, int p, int mid, int final): Student(first, last, sub) { paper = p; midterm = mid; finalExam = final; } char History::GetSubject() { } void History::Print(ostream& os) { char* fullName = strcat(firstName, " "); fullName = strcat(fullName, lastName); os.width(42); os << fullName; os.width(8); os << finalExam; os.width(8); os << Average(); switch (static_cast<int>(Average()) / 10) { case 10: case 9: os << 'A'; break; case 8: os << 'B'; break; case 7: os << 'C'; break; case 6: os << 'D'; break; default: os << 'E'; } os << '\n'; } double History::Average() { return static_cast<double>(paper*25 + midterm*35 + finalExam*40)/10000; } Math::Math(char* first, char* last, char sub, int q1, int q2, int q3, int q4, int q5, int t1, int t2, int final): Student(first, last, sub) { quizAvg = (q1, q2, q3, q4, q5)/5; test1 = t1; test2 = t2; finalExam = final; } char Math::GetSubject() { } void Math::Print(ostream& os) { char* fullName = strcat(firstName, " "); fullName = strcat(fullName, lastName); os.width(42); os << fullName; os.width(8); os << finalExam; os.width(8); os << Average(); switch (static_cast<int>(Average())/10) { case 10: case 9: os << 'A'; break; case 8: os << 'B'; break; case 7: os << 'C'; break; case 6: os << 'D'; break; default: os << 'E'; } os << '\n'; } double Math::Average() { return static_cast <double>(quizAvg*15 + test1*25 + test2*25 + finalExam*35)/10000; }
Code:#include <iostream> #include <fstream> #include <cstring> #include "student.h" using namespace std; void PrintHeader(ofstream& os, char sub); int main() { char first[21], last[21], fullName[42], subject; char* inFilename, *outFilename; int size, a, b, c, d, e, f, g, h, numE = 0, numH = 0, numM = 0; ifstream in1; ofstream out1; cout << "Please enter the name of the input file.\nFilename: "; cin >> inFilename; cout << "Please enter the name of the output file.\nFilename: "; cin >> outFilename; in1.open(inFilename); out1.open(outFilename); if (!in1) { cout << "Error: invalid input file name.\n"; exit(0); } in1 >> size; // read first line (size of file) // and declare new list of size Student *list = new Student[size]; for (int i = 0; i < size; i++) { in1 >> first >> last >> subject; if (subject == 'E') { in1 >> a >> b >> c >> d; English e(first, last, subject, a, b, c, d); list[i] = e; numE++; } if (subject == 'H') { in1 >> a >> b >> c; History h(first, last, subject, a, b, c); list[i] = h; numH++; } if (subject =='M') { in1 >> a >> b >> c >> d >> e >> g >> h; Math m(first, last, subject, a, b, c, d, e, f, g, h); list[i] = m; numM++; } } // print to output file out1 << "Student Grade Summary\n---------------------\n\n"; if (numE != 0) { PrintHeader(out1, 'E'); for (int i = 0; i < size; i++) { if (list[i].GetSubject() == 'E') list[i].Print(out1); } } if (numH != 0) { PrintHeader(out1, 'H'); for (int i = 0; i < size; i++) { if (list[i].GetSubject() == 'H') list[i].Print(out1); } } if (numM != 0) { PrintHeader(out1, 'M'); for (int i = 0; i < size; i++) { if (list[i].GetSubject() == 'M') list[i].Print(out1); } } delete[] list; in1.close(); out1.close(); return 0; } void PrintHeader(ofstream& os, char sub) { os << '\n'; if (sub == 'E') os << "ENGLISH CLASS\n\n"; else if (sub == 'H') os << "HISTORY CLASS\n\n"; else os << "MATH CLASS\n\n"; os.width(42); os << "Student"; os.width(8); os << "Final"; os.width(8); os << "Final"; os << "Letter\n"; os.width(42); os << "Name"; os.width(8); os << "Exam"; os.width(8); os << "Avg"; os << "Grade\n----------------------------------------------------------------\n"; }I'd appreciate any help.Code:student: student.o main.o g++ -o student student.o main.o student.o: student.cpp student.h g++ -c student.cpp main.o: main.cpp student.h g++ -c main.cpp clean: rm -f *.o student
