Read Data From File to Linked List C++

March 05, 2022 Post a Comment

Ok I take a file in it is a record of a persons first and last name. Format is like:
Trevor Johnson
Kevin Smith
Allan Harris

I need to read that file into program and so turn it into a linked list. So on the listing I can go Trevor, Kevin, Allan in a straight row but I can besides call out there terminal name when I am on their first proper noun in the listing. Lamentable if it doesn't make sense trying to explain all-time I tin.

So far I have

// list.cpp
// simple linked list program
#include <STDLIB.H>
#include <Cord>
#include <iostream>
#include <fstream>
#include <iomanip>
#include <cstdlib>
using std::cout;
using std::string;
using std::cin;
using std::ios;
using std::cerr;
using std::endl;
using std::setiosflags;
using std::resetiosflags;
using std::setw;
using std::setprecision;
using std::ifstream;
int listSearch = 0;
// node object for the linked list
struct Node {
cord data;
Node* nextWep;
Node* ammoForWep;
};
// implement a singly linked list
form LinkedList {protected:
Node* front; // arrow to the front of the linked list
Node* back; // pointer to the last node in the linked list
public:
// constructs an empty listing
LinkedList() {
front = back = NULL;
}
// deletes the list
~LinkedList() {
// remove objects from the listing equally long equally list is not empty
while(Length() > 0) {
RemoveFront();
}
}
// inserts a node at the front end of the listing
void InsertFrontWep(string newValue) {
Node* newNode = new Node;
newNode->data = newValue;
if (front == NULL) {
// list must exist empty so make front end & back point to new node
forepart = back = newNode;
newNode->nextWep= NULL;
} else {
// list is not empty then insert betwixt front end and outset node
newNode->nextWep = front;
front = newNode;
}
}
// search the listing for a target value
// return alphabetize if found or -ane if not found
int Search(string targetVal) {
Node* p;
int count = 0;
for (p = front; p != Null; p = p->link) {
if (p->data == targetVal) {
return count;
}
count++;
}
return -1;
}
// removes a node from the front of the listing
int RemoveFront() {
int returnVal;
Node *temp;
if (front end != Cypher) {
// list is not empty so remove & return first node
returnVal = front->data;
temp = front end;
front = front->link;
delete temp;
} else {
// list is empty simply return 0
returnVal = 0;
}
return returnVal;
}
// returns the length of the list
int Length() {
Node* p;
int count = 0;
// loop through each node in the listing until we notice a null value
for (p = front; p != NULL; p = p->link) {
count++;
}
return count;
}
// outputs a cord containing all the data values in the list
void Output() {
Node* p;
// loop through each node in the list until we find a zero value
for (p = front; p != NULL; p = p->link) {
cout << p->data << ", ";
}
}
};
// utilise inheritance to create a Prepare class from the LinkedList class
class Set : public LinkedList {
public:
// insert a new value only if it is unique (non already in the set)
int Search(string targetVal) {
Node* p;
int count = 0;
for (p = front; p != NULL; p = p->link) {
if (p->data == targetVal) {
return count;
}
count++;
}
return -ane;
}
void Insert(string newValue) {
Node* newNode = new Node;
newNode->data = newValue;
if (forepart == NULL) {
// list must be empty and so make front & back betoken to new node
forepart = dorsum = newNode;
newNode->link = Cipher;
} else {
listSearch = Search(newValue);
if(listSearch == -1)
{
// list is non empty so insert betwixt front end and showtime node
newNode->link = front;
front = newNode;
}
}
}
// make this the marriage of ii sets
void Matrimony(Fix& a, Fix& b) {
Node* p;
int search = 0;
for (p = a.forepart; p != Zero; p = p->link)
{
this->Insert(p->data);//u.Insert(p->information);
}
for (p = b.front; p != Naught; p= p->link)
{
search = this->Search(p->data);
if (search == -ane)
//u.Insert(p->data);
this->Insert(p->information);
}
}
// make this the intersection of two sets
void Intersection(Fix& a, Set& b)
{// Open Function
Node* p;
int search = 0;
for(p = a.front; p != NULL; p = p->link) { //Open up for statment
search = b.Search(p->data);
if(search != -one){ // Open if argument
//i.Insert(p->data);
this->Insert(p->data);
}
} // Close For statement
} // Shut Function
};
void main() {
ifstream inResources("resource.txt", ios::in);
if (!inResources)
{
cerr << "File could not be opened\n";
}
Set setA, setB, setUnion, setIntersection;
setA.Insert('1');
setA.Insert('ane');
setA.Insert('one');
setA.Insert('1');
setA.Insert('i');
cord text_line;
cout << "Contents of setA: ";
setA.Output();
cout << "\north\n";
setB.Insert('ane');
setB.Insert('ane');
setB.Insert('ane');
cout << "Contents of setB: ";
setB.Output();
cout << "\due north\due north";
setUnion.Union(setA, setB);
cout << "Contents of setA union setB: ";
setUnion.Output();
cout << "\n\n";
setIntersection.Intersection(setA, setB);
cout << "Contents of setA intersection setB: ";
setIntersection.Output();
cout << "\n\north";
}

Don't listen the principal I only was testing the list before hand. I don't want help with the whole consignment just looking for a push frontward in the right direction with that linked list.

Aug 10 '07 #1

crumpthiciall65.blogspot.com

Source: https://bytes.com/topic/c/answers/690762-reading-file-into-linked-list