I have read a csv file into my c++ program and applied linked list to it. I want to sort the order id column in the csv using linked list

Question

I'm sorry I had to write all of the unnecessary stuff. It wouldn't accept all this code otherwise.

I have read a csv file into my c++ program and applied linked list to it. I want to sort the order id column in the csv using linked list.

main.cpp

#include"iostream"
#include"string"
#include"fstream"
#include"node.h"
#include"linkedlist.h"
#include"bst.h"
#include"tree.h"
#include"string"
using namespace std;

BST tree;
linkedlist l;
Tree t;

void linklist();
void Binary_Search_Tree();


int main(){
    int choice;
    cout << "\nMenu:" << endl;
    cout << "1 Linked List  " << endl;
    cout << "2 Binary Tree  " << endl;
    cin >> choice;
    if (choice == 1){
        linklist();
        main();
    }
    else if (choice == 2){
        Binary_Search_Tree();
        main();
    }

    system("pause");
    return 0;
}

void linklist(){
    int choice;
    string country;
    string itemtype;
    string saleschannel;
    string orderdate;
    string orderid;
    string shipdate;
    cout << "\nMenu:" << endl;
    cout << "1 Add Node in Linked List           " << endl;
    cout << "2 Display in Linked List            " << endl;
    cout << "3 Search in Linked List             " << endl;
    cout << "4 Sort the Linked List              " << endl;
    cout << "5 Exit" << endl;

    cin >> choice;
    ifstream file("DataSet.csv");
    if (choice == 1){
        if (file.fail()){
            cout << "File is not open:" << endl;
        } else{
            file.is_open();
            while (!file.eof()){
                getline(file, country, ',');
                getline(file, itemtype, ',');
                getline(file, saleschannel, ',');
                getline(file, orderdate, ',');
                getline(file, orderid, ',');
                getline(file, shipdate, '\n');
                l.insert(country, itemtype, saleschannel, orderdate, orderid, shipdate);
            }

            file.close();
        }
        linklist();

    } else if (choice == 2){
        l.display();
        linklist();
    } else if (choice == 3){

        string id;
        cout << "\nEnter The Order ID:" << endl;
        cin.ignore();
        getline(cin, id);
        auto start = chrono::steady_clock::now();
        l.search(id);
        auto end = chrono::steady_clock::now();
        cout << "Progress time in nanoseconds  : " << chrono::duration_cast<chrono::nanoseconds> (end - start).count() << "ns " << endl;
        cout << "Progress time in microseconds : " << chrono::duration_cast<chrono::microseconds>(end - start).count() << " µs " << endl;
        cout << "Progress time in milliseconds : " << chrono::duration_cast<chrono::milliseconds>(end - start).count() << " ms " << endl;
        cout << "progress time in seconds      : " << chrono::duration_cast<chrono::seconds>     (end - start).count() << " sec" << endl;
        linklist();
    } else if(choice==4){
        l.sort(country);
        l.display();

    } else if (choice == 5){
        main();
    }

}

linkedlist.h

#pragma once
#include"iostream"
#include"node.h"
#include"string"
using namespace std;

class linkedlist{
private:
    node*head;
    node*tail;
public:
    linkedlist();
    void insert(string, string, string, string, string, string);
    void search(string);
    void sort(string);
    void display();
};

linkedlist.cpp

#include"iostream"
#include"linkedlist.h"
#include"string"
using namespace std;

linkedlist::linkedlist(){
    head = NULL;
    tail = NULL;
}

void linkedlist::insert(string country, string item, string sales, string orderdate, string orderid, string shipdate){
    if (head == NULL){
        node*newnode = new node(country, item, sales, orderdate, orderid, shipdate);
        head = newnode;
        tail = newnode;
    }
    else {
        node*newnode = new node(country, item, sales, orderdate, orderid, shipdate);
        tail->setnext(newnode);
        tail = newnode;

    }
}

void linkedlist::display(){
    node*temp;
    temp = head;

    while (temp != NULL){
        cout << "Country Name Is:" << temp->getcountry()      << endl;
        cout << "Item Type    Is:" << temp->getitemtype()     << endl;
        cout << "Channel Sales Is:" << temp->getsaleschanel()  << endl;
        cout << "Order Date   Is:" << temp->getorderdate()    << endl;
        cout << "Order Id     Is:" << temp->getorderid()      << endl;
        cout << "Ship Date    Is:" << temp->getshipdate()     << endl;
        temp = temp->getnext();
    }

}

void linkedlist::search(string orderid){
    node*temp;
    temp = head;

    while (temp != NULL){
        if (temp->getorderid() == orderid){
            break;
        } else{
            temp = temp->getnext();
        }
    }

    cout << "Country Name Is:" << temp->getcountry()     << endl;
    cout << "Item Type    Is:" << temp->getitemtype()    << endl;
    cout << "Chanel Sales Is:" << temp->getsaleschanel() << endl;
    cout << "Order Date   Is:" << temp->getorderdate()   << endl;
    cout << "Order Id     Is:" << temp->getorderid()     << endl;
    cout << "Ship Date    Is:" << temp->getshipdate()    << endl;
}

I have read a csv file into my c++ program and applied linked list to it. I want to sort the order id column in the csv using linked list.

I'm sorry I had to write all of this. It wouldn't accept all this code otherwise.

Answer 1

I will just give some feedback about your program.

I assume the intention was not make the call flow to main()-> linklist() recursive. The main() is calling main(), and linklist() is also calling main() and linklist()

if (choice == 1){
    linklist();
    main();
}
else if (choice == 2){
    Binary_Search_Tree();
    main();
}

I would rewrite this to something simple like:

while(true) {
   linklist();
}

And in linklist() function remove all calls to main() and linklist(), and on choice 5 just:

}  else if (choice == 5) {
   exit(0); // Exit application
}

I would also try to find a better suitable name for the function 'linklist()'

In the C++ STL library equivalent to a linked list there is std::list ( https://en.cppreference.com/w/cpp/container/list ) - which is preferable to use - if the case is that you really need to use a linked-list - or is this just an exercise where you want to learn how to write your own linked-list?

That said, the advantage of a linked-list is constant time insert and delete, but very poor random access performance. Taking into account CPU cache, as the elements may not be on a linear chunk in memory, cache-misses may lead to poor performance, however this a big topic, that I will not get into here.

For your application I would not use a linked-list at all, I would just use std::vector ( https://en.cppreference.com/w/cpp/container/vector ) Just use std::sort ( https://en.cppreference.com/w/cpp/algorithm/sort ) to sort the elements in the list. I estimate that under ~100000 elements you will probably not have any performance issues, just using std::vector and std::sort