如何通过键盘或分数文件输入分数

这些作业的更好方法是使用一个记录容器，而不是每个元素的几个容器。

让我们将记录定义为：

struct Score_Record
{
  std::string first_name;
  std::string last_name;
  int score;
};

为简单起见，让我们选择一个向量作为容器。为了保存击键，我们将使用typedef：

typedef std::vector<Score_Record> Container_Type;

如果我们希望能够从文件或键盘加载记录，我们将使用通用流的概念：

void Input_Score(std::istream& input, Score_Record& sr)
{
  input >> sr.first_name;
  input >> sr.last_name;
  input >> sr.score;
  input.ignore(100000, 'n'); // Synchronize to next input line.
}

so，要从键盘输入：

Score_Record sr;
Input_Record(cin, sr);

从文件输入：

ifstream data_file("my_data.txt");
Input_Record(data_file);

这是一些可以找到最大分数的代码：

Container_Type  database;
// read into database
const size_t quantity = database.size();
int maximum_score = -1;
for (unsigned int i = 0; i < quantity; ++i)
{
  if (database[i].score > maximum_score)
  {
    maximum_score = database[i].score;
  }
}

最低，平均值和平均值可以与上述循环相似。

编辑1：更简单的解决方案
如果我们承担与班级有关的所有事物分数的责任，我们可以让班级从输入流读取其值：

class Score_Record
{
  public:
    Score_Record()
    { ; }
    virtual ~Score_Record();
    friend std::istream& operator>>(std::istream& input, Score_Record& sr);
  private:
    std::string first_name;
    std::string last_name;
    int         score;
};
std::istream& operator>>(std::istream& input, Score_Record& sr)
{
  input >> sr.first_name;
  input >> sr.last_name;
  input >> sr.score;
  input.ignore(100000, 'n'); // synchronize to next text line.
  return input;
}

从文件中读取单个Score_Record：

Score_Record sr;
data_file >> sr;

将整个文件读取到数据库中：

Container_Type database;
while (database >> sr)
{
  database.push_back(sr);
}

#include <iostream>
#include <string>
#include <fstream>
using namespace std;
void getInformationKeyBoard(int size, string Names[], int socres[]);
void getName(string & name);
int main()
{
    const int size = 1024;
    string Name[size];
    int score[size];
    int NumberOfStudent;
    char choice;
    cout << "You want to enter your scores by your keyboard (A) or from your input (B): ";
    cin >> choice;
    if (choice == 'a' || choice == 'A') // It will take information from keyboard
    {
        cout << "How many students do you want to enter: ";
        cin >> NumberOfStudent;
        getInformationKeyBoard(NumberOfStudent, Name, score);
    }
    else if (choice == 'b' || choice == 'B') // It will take information from file
    {
        string NameA;
        getName(NameA);
        GetInformationFile(nameA, NumberOfStudent, Name, score); // This is where my program get an error


    }
    else // If you choice is not A,a or B,b
        cout << "Your did not follow the right instruction.";

    cout << endl << endl;
    system("pause");
    return 0;
}
void getInformationKeyBoard(int size, string Names[], int scores[]) // Information from keyboard
{
    for (int i = 0; i < size; i++)
    {
        cout << i + 1 << ". Student First Name and Last Name: ";
        cin.ignore();
        getline(cin, Names[1]);
        do
        {
            cout << i + 1 << ". Enter the score between 1 and 100: ";
            cin >> scores[i];
        } while (scores[i] > 100 || scores[i] < 0 );
    }
}
void GetInformationFile(fstream name, int size, string Names[], int scores[])
{
    for (int i = 0; i < size; i++)
    {
        string line;
        getline(name, line);
            Names[i];
            scores[i];
    }
}


void getName(string & name)
{
    char again = 'Y';
    bool close = false;
    while (close == false)
    {
    cout << "Enter name of file: ";
    cin >> name;
    ifstream inFile;
    inFile.open(name.c_str());
    close = true;
    if (!inFile)
    {
        cout << "File did not open correctly" << endl;
        do 
        {
            cout << "Do you want to do it again(Y) or Close (N):  ";
            cin >> again;
        } 
        while (again != 'y' && again != 'Y' && again != 'n' && again != 'N');
        if (again == 'y' || again == 'Y')
            close = false;
        else
            close = true;
    }
    }
}