Question

我在底层代码（kontener.h，函数void List :: push）中有问题，这似乎是一个简单的错误，但是我现在呆了几个小时。我有另一个标头，但未在此处发布，因为我认为该标头对问题没有影响（可能是错误的）

MAIN.CPP

#include <iostream>
#include <stdexcept>
#include <string>
#include <sstream>
#include <fstream>
#include "student.h"
#include "kontener.h"
using namespace std;

int main()
{
    List < Student > S;

    fstream GRA("GRA.txt", ios::in);
    if (!GRA.good())
        throw logic_error("Nie znaleziono pliku GRA.TXT");
    fstream SID("SID.txt", ios::in);
    if (!SID.good())
        throw logic_error("Nie znaleziono pliku SID.TXT");

    while (!GRA.eof())
    {
        string nazwisko;
        string imie;
        string imie2;
        int index;
        int ocena;
        GRA >> nazwisko;
        GRA.ignore();
        GRA >> imie;
        ;
        GRA.ignore();
        GRA >> imie2;
        GRA.ignore();
        GRA >> index;
        GRA.ignore();
        GRA >> ocena;

        try
        {
            Student s1;
            s1.setNazwisko(nazwisko);
            s1.setImie(imie);
            s1.setImie2(imie2);
            s1.setIndex(index);
            s1.setOcena(ocena);
            S.push(s1);
        }
        catch (exception &e)
        {
            cout << e.what() << endl;
        }

    }

    GRA.close();
    SID.close();

    fstream INF("INF.TXT", ios::out);

    int counter = S.size();

    for (int i = 0; i < counter; i++)
    {
        Student s1 = S.pop();
        INF << s1.getIndex() << ";" << s1.getOcena() << ";" << s1.getNazwisko()
                << " " << s1.getImie() << "." << s1.getImie2();

    }

    INF.close();

}

Kontener.h（此文件中有错误）错误：“ operator>”不匹配（操作数类型为“ Student”和“ Student”

#ifndef KONTENER_H_INCLUDED
#define KONTENER_H_INCLUDED
#include <iostream>
#include <stdexcept>
#include <string>
#include <sstream>
#include <fstream>
using namespace std;

template<typename T>
struct List
{
private:
    struct Node
    {
        T value;
        Node *next;
        Node(T v, Node *n = nullptr)
        {
            value = v;
            next = n;
        }
    };
    Node *head;
    int counter;
public:
    List();

    ~List();

    T pop();

    void push(T x);

    int size() const;

};

template<typename T>
List<T>::List()
{
    head = nullptr;
    counter = 0;
}

template<typename T>
List<T>::~List()
{
    while (head != nullptr)
    {
        Node *killer = head;
        head = head->next;
        delete killer;
    }
    counter = 0;
}

template<typename T>
T List<T>::pop()
{
    if (counter != 0)
    {
        Node *killer = head;
        T x = killer->value;
        head = head->next;
        delete killer;
        counter--;
        return x;
    }
    else
        throw logic_error("Empty list.");
}

template<typename T>
int List<T>::size() const
{
    return counter;
}

template<typename T>
void List<T>::push(T x)
{
    Node *pred = nullptr;
    Node *succ = head;

    while (succ!=0 && succ->value > x)  // ERROR OCCURS HERE
    {   
        pred=succ;
        succ=succ->next;
    }

    Node *creator = new Node(x, succ);
    if (pred == nullptr)
    {
        head = creator;
    }
    else
    {
        pred->next = creator;
    }
    counter++;
}

#endif // KONTENER_H_INCLUDED

Answer 1

succ->value和x的类型为Student。您正在尝试对这些操作符使用运算符，尤其是运算符>。您的编译器告诉您，没有为两个operator>类型的值定义Student。

您需要自己实施操作员。

此类操作员的签名如下：

inline bool operator> (const Student& s1, const Student& s2);

或作为Student类本身的成员：

inline bool operator> (const Student& other) const;

您还可以先搜索您的项目，以检查运算符是否确实在某个地方实现了，以及您只是没有包含适当的标头。

错误：“操作符>”不匹配（操作数类型为“学生”和“学生”

1 个答案: