Program only prints the first few lines of the input file

May 31, 2024

In multiple compilers it prints only 7 lines from the file but there are MANY more lines but logically and syntax-wise the code looks good to me. Am I missing something? At first I thought it was the compiler but now I feel like there could be something wrong with my code.

#include <iostream>
#include <string> 
#include <sstream>
#include <fstream>
using namespace std;

class Employee { // employee class
public:
    int employeeId;
    string firstName;
    string lastName;
    string phoneNumber;
    string emailAddress;
    double salary;

    Employee(int id, string first, string last, string phone, string email, double sal)             // employee class constructor 
        :employeeId(id), firstName(first), lastName(last), phoneNumber(phone), emailAddress(email), salary(sal) {}

    void display() { // used to display an object of the employee class
        cout << "Id: " << employeeId << ", Name: " << firstName << " " << lastName
            << ", Phone Number: " << phoneNumber << ", Email: " << emailAddress
            << ", Salary: " << salary << endl;
    }
};


class Node { // class for each node of the linked list 
public:
    Employee* info;
    Node* next;

    Node(Employee* emp) : info(emp), next(nullptr) {}
};

class LinkedList { //the link list class itself 
private:
    Node* head;
public:
    LinkedList() : head(nullptr) {} // constructopr that initializes the list with no contents (empty)

    void insert(Employee* emp) {
        Node* newNode = new Node(emp);
        if (head == nullptr || head->info->employeeId >= newNode->info->employeeId) {
            newNode->next = head;
            head = newNode;
        }
        else {
            Node* current = head;
            while (current->next != nullptr && current->next->info->employeeId < newNode->info->employeeId) {
                current = current->next;
            }
            newNode->next = current->next;
            current = current->next;

        }
    }


    void display() { // function that displays the nodes of the link list 
        Node* current = head;
        while (current != nullptr) {
            current->info-> display();
            current = current->next;
        }
    }

    ~LinkedList() {
        Node* current = head;
        while (current != nullptr) {
            Node* next = current->next;
            delete current;
            current = next;
        }
    }
};

// Now that all three classes are created and the functions needed with them, 
// we can now read from the file and add the employees to the linked list 
void readFile(const string& filename, LinkedList& list) {
    ifstream file(filename);
    if (!file.is_open()) {
        cerr << "Error opening file: " << filename << endl;
        return;
    }

    string line;
    while (getline(file, line)) {
        stringstream ss(line);
        int id;
        string firstName, lastName, phoneNumber, emailAddress;
        double salary;
        ss >> id >> firstName >> lastName >> phoneNumber >> emailAddress >> salary;
        Employee* emp = new Employee(id, firstName, lastName, phoneNumber, emailAddress, salary);
        list.insert(emp);
    }
    file.close();
}
int main() {
    LinkedList list;
    readFile("Week 1-employeeDataset_Project 1.txt", list);
    list.display();
    return 0;
}

A sample line from the input file looks like this.

12690 Glynis Filipson 539-917-2209 gfilipson56@liveinternet.ru 105401.55

I believe the main issue if anything may lie in the read file function (above).

>Solution :

Your insert function is wrong. In the else you have:

Node* current = head;
while (current->next != nullptr && current->next->info->employeeId < newNode->info->employeeId) {
    current = current->next;
}
newNode->next = current->next;
current = current->next;

At the end of this nothing in the linked list points to newNode, meaning it wasn’t actually inserted. I can’t test this right now, but I believe the last line should instead be