Question

我迫切需要帮助。我应该使用结构和向量创建学生记录。在该计划中，我应该：

对于特定学生，通过姓名或学号识别（a）在记录中输入新学生。（假设没有完成课程。）（b）平均成绩点（c）成绩单，即所取得的课程清单，包括所获得的学分和成绩（d）记录新完成的课程
所有参加过特定课程的学生的名单，按名称排序。
所有学生及其平均成绩的平均排名，按成绩点平均排序，谁正在试用，即平均分等级< 2.0。

这就是我到目前为止......我似乎遇到了用户输入的麻烦，如何将其读入我的结构

using namespace std;

struct courses {
    string courseName;
    int courseNum;
    double credit;
    char grade;
};

struct students {
    string name;
    int id;
    vector<courses> c;
};

int main() {

    // variables
    string name;
    char selector;
    students s;
    courses d;
    vector<students> student;
    vector<courses> course;

    // (1) create a menu: (a) user input, (b) echo record (with overall gpa), (c) failed students
    do {
        // prompt for user input
        cout << "Enter Q to (Q)uit, (C)reate new student record, (S)how all record(s) on file, show students on (P)robation: ";
        cin >> selector;

        selector = toupper(selector);
        switch (selector) {



            // (a) ask and get for user input:
            // student info first
            // courses second
        case 'C':

            // variables within case C
            char answer;
            char answerAddAnotherCourseEntry;
            char answerToAnotherStudentRecord;

            do {


                cout << "Enter your name and student ID number: ";
                cin >> s.name >> s.id;
                student.push_back(s);

                do {
                    cout << "Do you want to create a student course entry ('y' or 'n')? ";
                    cin >> answer;
                    answer = toupper(answer);

                    cout << "Enter your course number, course name, grade received and credit worth: ";
                    cin >> d.courseNum >> d.courseName >> d.grade >> d.credit;
                    course.push_back(d);


                    cout << "Add another student course entry ('y' or 'n'): ";
                    cin >> answerAddAnotherCourseEntry;
                    answerAddAnotherCourseEntry = toupper(answerAddAnotherCourseEntry);


                } while (answer == 'N');

                cout << "Add another student record ('y' or 'n'): " << endl;
                cin >> answerToAnotherStudentRecord;
                answerAddAnotherCourseEntry = toupper(answerToAnotherStudentRecord);
            } while (answerToAnotherStudentRecord == 'N');
            break;


            // (b) echo record of vectors
            // sort by name
        case 'S':
            if (student.empty()) {
                cout << "\nSorry, no records exist in the database.";
            }
            else
                for (int count = 0; count < student.size(); count++) {         //For Loop to Display All Records

                    cout << "Student name: " << student[count].name << "ID Number: " << student[count].id << endl;
                    count++;

                    // another for loop i think
                    for (int i = 0; i < course.size(); i++) {
                        cout << "Course info: " << " " << course[i].courseNum << " " << course[i].courseName << " " << course[i].credit << " " << course[i].grade << endl;
                        i++;
                    }
                }
            cout << endl;
            break;


            // (c) separate failed student into another vector
            // sort by gpa
        case 'P':
            break;




        } // bracket closing switch
    } // bracket closing do while
    while (selector != 'q' && selector != 'Q');     // first do while

Answer 1

我在输入中看到的问题是您试图将用户输入直接存储在字符串中，例如，在结构name的变量s中：

cout << "Enter your name and student ID number: ";
cin >> s.name >> s.id;

这不编译。相反，您可以先将名称存储在临时char数组中，然后将其复制到s.name。

char studentName[128];
cout << "Enter your name and student ID number: ";
cin >> studentName >> s.id;
s.name = studentName;

如果您想直接将输入存储在字符串中，也可以使用getline()。

此外，您尝试直接将变量student[count].name输出到cout：

cout << "Student name: " << student[count].name << "ID Number: " << student[count].id << endl;

首先将字符串转换为char数组进行编译：

cout << "Student name: " << student[count].name.c_str() << "ID Number: " << student[count].id << endl;

C ++：学生记录计划

1 个答案: