c++ - 无法使 strstr() 工作

Question

我有一个家庭作业，我在一个区域根本无法正确工作，特别是在我尝试比较字符串的地方。这是作业:

You will write a program that prompts the user for student names, ages, gpas, and graduation dates. Your program will then read in all the student information and store them into a linked list. The program will then print the names of the students. Next, the program will prompt the user for a string. The program will print the complete information for each student containing the string in the name.

这是我所拥有的:

#include <iostream>
#include <cstring>
using namespace std;
const char NAME_SIZE = 50;
struct StudentInfo
{
   char studentName[NAME_SIZE];
   int age;
   double gpa;
   char graduationSemester[3];
   StudentInfo *next;
};
void displayStudentNames(StudentInfo *top);
void displayStudentInfo(StudentInfo *top);

int main(){
    StudentInfo *top = 0;
    cout << "Please enter the students. Enter the name, age, gpa, and semester of graduation (e.g. F13)." << endl;
    cout << "Enter an empty name to stop." << endl << endl;
    bool done = false;
    while(!done){
        char nameBuffer[NAME_SIZE];
        char graduationBuffer[3];
        cin.getline(nameBuffer, NAME_SIZE);
        if(nameBuffer[0] != 0){
            StudentInfo *temp = new StudentInfo;
            strcpy(temp->studentName, nameBuffer);
            cin >> temp->age;
            cin >> temp->gpa;
            cin.getline(graduationBuffer, 3);
            strcpy(temp->graduationSemester, graduationBuffer);
            cin.ignore(80, '\n');
            temp->next = top;
            top = temp;
        }else{
            displayStudentNames(top);
            displayStudentInfo(top);
            done = true;
        }
    }
}

void displayStudentNames(StudentInfo *top){
    cout << "Here are the students that you entered: " << endl << endl;
    while(top){
        cout << top->studentName << endl;
        top = top->next;
    }
    cout << endl;
}

void displayStudentInfo(StudentInfo *top){
    char name[NAME_SIZE];
    do{
        cout << "Which students do you want? ";
        cin.getline(name, NAME_SIZE);
        const char *str = top->studentName;
        const char *substr = name;
        const char *index = str;
        while((index = strstr(index,substr)) != NULL){
            cout << "Name: " << top->studentName << ", Age: " << top->age << ", GPA: " << top->gpa << ", Graduations Date: " << top->graduationSemester;
            index++;
        }
    }while(name[0] != 0);
}

我的问题出在 displayStudentInfo 函数中，我无法使其正常工作。我尝试过很多不同的东西，这只是我尝试过的最新的东西。但是在程序前面创建链表后，我们应该输入一个从字母到全名的字符串，并在列表中的任何位置找到它，然后打印出该特定名称的信息。

eta:我的链表向后存储结构也有问题？它也没有存储我的毕业日期，或者当我尝试打印它们时出现问题，因为它们打印为空白。

Answer 1

您的代码问题很明显。您只是检查列表的头部，而不是遍历列表。

这是有问题的部分(假设每个函数调用应该返回 1 名学生的信息):

void displayStudentInfo(StudentInfo *top){
    char name[NAME_SIZE];

    //Addes 'node' variable for simplicity, you can use 'top' itself
    StudentInfo *node = top;

    cout << "Which students do you want? ";
    cin.getline(name, NAME_SIZE);
    do{
        // Check if name is correct
        // "Entered name should be at start of field"
        // You should use == not =
        if(node->studentName == strstr(node->studentName, name){
            cout << "Name: " << top->studentName << ", Age: " << top->age << ", GPA: " << top->gpa << ", Graduations Date: " << top->graduationSemester;
        }
        // Traverse in list
        node = node->next;
        // Until reach end of list
    }while(node != NULL);
}