It is necessary to remake the program, so that we can choose for each student their number of subjects. s ++

Question

HERE IS THE TASK

Introduce several student records with fields:

Student's name

Record number Scholarship size

Array of structures "Subject"

The "Subject" structure has the following fields:

Teacher's name

Item Name

Evaluation

Write a program that performs the following actions:

- establishes scholarships for all students who study at 4 and 5

- sorts the structures in the order of growth of the average score (the direction of sorting is chosen by the user)

#include "stdafx.h" #include <iostream> #include <iomanip> using namespace std; //Количество предметов в зачетке const int subjectsCountInRecordBook = 2; //Размер стипендии const int paymentValue = 2000; struct Subject { char SubjName[30]; char SurnameTeacher[20]; int Mark; }; struct RecordBook { int Id; char SurnameStudent[30]; Subject Subjects[subjectsCountInRecordBook]; double Payment; double avgMark; }; int main() { int studentsCount; cout << "Enter count of students: "; cin >> studentsCount; cout << endl; //Создаем пустые зачетки по количеству стедентов RecordBook *recordBooks = new RecordBook[studentsCount]; //Заполняем информацию о предметах во временный контейнер Subject subjectsContainer[subjectsCountInRecordBook]; for (int i = 0; i < subjectsCountInRecordBook; i++) { cout << "Enter" << (i + 1) << " subject name: "; cin >> subjectsContainer[i].SubjName; cout << "Enter" << (i + 1) << "Surname Teacher: "; cin >> subjectsContainer[i].SurnameTeacher; cout << endl; } //Начинаем заполнять зачетки для каждого студента for (int i = 0; i < studentsCount; i++) { cout << "Enter" << (i + 1) << " student's lastname: "; cin >> recordBooks[i].SurnameStudent; cout << "Enter" << (i + 1) << " record book id: "; cin >> recordBooks[i].Id; //Сумма оценок по всем предметам в зачетке int sumMark = 0; //Нужно ли платить стипендию этому стедунту? bool needPayment = true; //Скопируем данные из контейнера в зачетку и впишем оценки по предметам for (int j = 0; j < subjectsCountInRecordBook; j++) { strcpy_s(recordBooks[i].Subjects[j].SubjName, subjectsContainer[j].SubjName); strcpy_s(recordBooks[i].Subjects[j].SurnameTeacher, subjectsContainer[j].SurnameTeacher); cout << "Enter" << (i + 1) << " student's mark of " << recordBooks[i].Subjects[j].SubjName << ": "; cin >> recordBooks[i].Subjects[j].Mark; //Установим стипндии для тех кто учится на 4 и 5 if (recordBooks[i].Subjects[j].Mark < 4) needPayment = false; //считаем и заполняем средний балл в зачетке sumMark += recordBooks[i].Subjects[j].Mark; recordBooks[i].avgMark = (double)sumMark / (double)subjectsCountInRecordBook; } if(needPayment == true) recordBooks[i].Payment = paymentValue; else recordBooks[i].Payment = 0; } //Выбор типа сортировки int sort_type; while (true) { cout << "Choose sort type(0 for ascending; 1 for descending): "; cin >> sort_type; cout << endl; if (sort_type != 0 && sort_type != 1) { cout << "Unknown sort type." << endl; continue; } break; } //===Сортировка зачеток=== for (int i = 0; i < studentsCount - 1; i++) { for (int j = 0; j < studentsCount - i - 1; j++) { RecordBook temp; if ((sort_type == 0 && recordBooks[j].avgMark > recordBooks[j + 1].avgMark) || (sort_type == 1 && recordBooks[j].avgMark < recordBooks[j + 1].avgMark)) { temp = recordBooks[j]; recordBooks[j] = recordBooks[j + 1]; recordBooks[j + 1] = temp; } } } //Выводим отсортированный массив зачеток на экран cout << "=========Sorted=record=books=============" << endl; for (int i = 0; i < studentsCount; i++) { cout << "Student Surname: " << recordBooks[i].SurnameStudent << endl; cout << fixed; cout << setprecision(2); cout << "Avg Mark: " << recordBooks[i].avgMark << endl; cout << "Record book Id: " << recordBooks[i].Id << endl; cout << "Payment: " << recordBooks[i].Payment << endl; //Инфа по предметам cout << "Subjects info:"; cout << endl; for (int j = 0; j < subjectsCountInRecordBook; j++) { cout << "\tSubject:" << recordBooks[i].Subjects[j].SubjName << ", Teacher:" << recordBooks[i].Subjects[j].SurnameTeacher << ", Mark:" << recordBooks[i].Subjects[j].Mark << endl; } cout << "==================" << endl; } delete[] recordBooks; system("pause"); return 0;

}

HERE'S TASK Enter several structures "Student Records" with fields: Student's Name Record Number Scholarships Array of Structures "Subject Structure" Subjects "has fields: Teacher's name Name of subject Assessment Write a program that performs the following actions: sets scholarships for all students who study on 4 and 5 sorts structures in the order of growth of the average score (the direction of sorting is selected by the user)
It seems that you need to use the list here, but I do not quite understand how, could you help?

Accepted Answer · 2018-04-25T06:58:11

Yes, there is nothing special and nothing to redo.

You add the input of the number of subjects (by analogy with the input of the number of students), and do not forget to select and clean up the memory for yourself (by analogy with the array of credits). Everything.

The example introduces the number of subjects for all students. If you need the number of subjects for students to be different (one has 2, another has 4) - add a field with the number of subjects to the structure of the class, for each student I enter the number of his subjects and the subjects themselves.

Another option is when your subjects are fixed - 10 pieces, but each student has his own subjects (some subset of the set of original subjects). Then start the id field for the subject structure, and when entering a student, ask for the number of subjects, and then to enter each subject, ask for the subject's id and grade for the subject.

If possible - all this can be rewritten using classes and std :: string, then you can use lists and vectors from STL: std::list and std::vector , which simplifies the tasks of working with memory.

 #include "stdafx.h" #include <iostream> #include <iomanip> using namespace std; //Количество предметов в зачетке int subjectsCountInRecordBook = 0; //Размер стипендии const int paymentValue = 2000; struct Subject { char SubjName[30]; char SurnameTeacher[20]; int Mark; }; struct RecordBook { int Id; char SurnameStudent[30]; Subject* Subjects; double Payment; double avgMark; }; int main() { int studentsCount; cout << "Enter count of students: "; cin >> studentsCount; cout << "Enter count of subject:"; cin >> subjectsCountInRecordBook; cout << endl; //Создаем пустые зачетки по количеству стедентов RecordBook *recordBooks = new RecordBook[studentsCount]; //Выделяем память под предметы в зачётке for (int i = 0; i < studentsCount; i++){ recordBooks[i].Subjects = new Subject[subjectsCountInRecordBook]; } //Заполняем информацию о предметах во временный контейнер Subject* subjectsContainer = new Subject[subjectsCountInRecordBook]; for (int i = 0; i < subjectsCountInRecordBook; i++) { cout << "Enter" << (i + 1) << " subject name: "; cin >> subjectsContainer[i].SubjName; cout << "Enter" << (i + 1) << "Surname Teacher: "; cin >> subjectsContainer[i].SurnameTeacher; cout << endl; } //Начинаем заполнять зачетки для каждого студента for (int i = 0; i < studentsCount; i++) { cout << "Enter" << (i + 1) << " student's lastname: "; cin >> recordBooks[i].SurnameStudent; cout << "Enter" << (i + 1) << " record book id: "; cin >> recordBooks[i].Id; //Сумма оценок по всем предметам в зачетке int sumMark = 0; //Нужно ли платить стипендию этому стедунту? bool needPayment = true; //Скопируем данные из контейнера в зачетку и впишем оценки по предметам for (int j = 0; j < subjectsCountInRecordBook; j++) { strcpy_s(recordBooks[i].Subjects[j].SubjName, subjectsContainer[j].SubjName); strcpy_s(recordBooks[i].Subjects[j].SurnameTeacher, subjectsContainer[j].SurnameTeacher); cout << "Enter" << (i + 1) << " student's mark of " << recordBooks[i].Subjects[j].SubjName << ": "; cin >> recordBooks[i].Subjects[j].Mark; //Установим стипндии для тех кто учится на 4 и 5 if (recordBooks[i].Subjects[j].Mark < 4) needPayment = false; //считаем и заполняем средний балл в зачетке sumMark += recordBooks[i].Subjects[j].Mark; recordBooks[i].avgMark = (double)sumMark / (double)subjectsCountInRecordBook; } if(needPayment == true) recordBooks[i].Payment = paymentValue; else recordBooks[i].Payment = 0; } //Выбор типа сортировки int sort_type; while (true) { cout << "Choose sort type(0 for ascending; 1 for descending): "; cin >> sort_type; cout << endl; if (sort_type != 0 && sort_type != 1) { cout << "Unknown sort type." << endl; continue; } break; } //===Сортировка зачеток=== for (int i = 0; i < studentsCount - 1; i++) { for (int j = 0; j < studentsCount - i - 1; j++) { RecordBook temp; if ((sort_type == 0 && recordBooks[j].avgMark > recordBooks[j + 1].avgMark) || (sort_type == 1 && recordBooks[j].avgMark < recordBooks[j + 1].avgMark)) { temp = recordBooks[j]; recordBooks[j] = recordBooks[j + 1]; recordBooks[j + 1] = temp; } } } //Выводим отсортированный массив зачеток на экран cout << "=========Sorted=record=books=============" << endl; for (int i = 0; i < studentsCount; i++) { cout << "Student Surname: " << recordBooks[i].SurnameStudent << endl; cout << fixed; cout << setprecision(2); cout << "Avg Mark: " << recordBooks[i].avgMark << endl; cout << "Record book Id: " << recordBooks[i].Id << endl; cout << "Payment: " << recordBooks[i].Payment << endl; //Инфа по предметам cout << "Subjects info:"; cout << endl; for (int j = 0; j < subjectsCountInRecordBook; j++) { cout << "\tSubject:" << recordBooks[i].Subjects[j].SubjName << ", Teacher:" << recordBooks[i].Subjects[j].SurnameTeacher << ", Mark:" << recordBooks[i].Subjects[j].Mark << endl; } cout << "==================" << endl; } for (int i = 0; i < studentsCount; i++){ delete[] recordBooks[i].Subjects; } delete[] recordBooks; delete[] subjectsContainer; system("pause"); return 0; }

Conclusion:

 Enter count of students: 2 Enter count of subject:3 Enter1 subject name: OOP Enter1Surname Teacher: Egorov Enter2 subject name: AIG Enter2Surname Teacher: Ivanova Enter3 subject name: TOE Enter3Surname Teacher: Karlova Enter1 student's lastname: Petrov Enter1 record book id: 1 Enter1 student's mark of OOP: 4 Enter1 student's mark of AIG: 5 Enter1 student's mark of TOE: 4 Enter2 student's lastname: Sidorov Enter2 record book id: 2 Enter2 student's mark of OOP: 3 Enter2 student's mark of AIG: 5 Enter2 student's mark of TOE: 5 Choose sort type(0 for ascending; 1 for descending): 1 =========Sorted=record=books============= Student Surname: Petrov Avg Mark: 4.33 Record book Id: 1 Payment: 2000.00 Subjects info: Subject:OOP, Teacher:Egorov, Mark:4 Subject:AIG, Teacher:Ivanova, Mark:5 Subject:TOE, Teacher:Karlova, Mark:4 ================== Student Surname: Sidorov Avg Mark: 4.33 Record book Id: 2 Payment: 0.00 Subjects info: Subject:OOP, Teacher:Egorov, Mark:3 Subject:AIG, Teacher:Ivanova, Mark:5 Subject:TOE, Teacher:Karlova, Mark:5 ==================

The example introduces the number of subjects for all students.
"If you need the number of subjects for students to be different (one has 2, another has 4), add a field with a number of subjects to the structure of the class, for each student I enter the number of his subjects and the subjects themselves."
@ AlinaGordeeva Well, yes, as long as you can only ask questions =) Write down what exactly does not work.
The author of the code attached to the question would easily solve this problem.
Even if he had problems with the allocation of dynamic arrays - in my answer he would have spied how to do it.

It is necessary to remake the program, so that we can choose for each student their number of subjects. s ++

1 answer 1

More articles: