C++ Linked List - Reading data from a file with a sentinel
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Published on 2012-10-30T22:46:24Z
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2012/10/30
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Hit count: 260
So I've done quite a bit of research on this and can't get my output to work correctly. I need to read in data from a file and have it stored into a Linked List. The while loop used should stop once it hits the $$$$$ sentinel. Then I am to display the data (by searching by ID Number[user input]) I am not that far yet I just want to properly display the data and get it read in for right now.
My problem is when it displays the data is isn't stopping at the $$$$$ (even if I do "inFile.peek() != EOF and omit the $$$$$) I am still getting an extra garbage record.
I know it has something to do with my while loop and how I am creating a new Node but I can't get it to work any other way.
Any help would be appreciated.
students.txt
Nick J Cooley
324123
60
70
80
90
Jay M Hill
412254
70
80
90
100
$$$$$
assign6.h file
#pragma once
#include <iostream>
#include <string>
using namespace std;
class assign6
{
public:
assign6(); // constructor
void displayStudents();
private:
struct Node
{ string firstName;
string midIni;
string lastName;
int idNum;
int sco1; //Test score 1
int sco2; //Test score 2
int sco3; //Test score 3
int sco4; //Test score 4
Node *next;
};
Node *head;
Node *headPtr;
};
assign6Imp.cpp // Implementation File
#include "assign6.h"
#include <fstream>
#include <iostream>
#include <string>
using namespace std;
assign6::assign6() //constructor
{
ifstream inFile;
inFile.open("students.txt");
head = NULL;
head = new Node;
headPtr = head;
while (inFile.peek() != EOF) //reading in from file and storing in linked list
{
inFile >> head->firstName >> head->midIni >> head->lastName;
inFile >> head->idNum;
inFile >> head->sco1;
inFile >> head->sco2;
inFile >> head->sco3;
inFile >> head->sco4;
if (inFile != "$$$$$")
{
head->next = NULL;
head->next = new Node;
head = head->next;
}
}
head->next = NULL;
inFile.close();
}
void assign6::displayStudents()
{
int average = 0;
for (Node *cur = headPtr; cur != NULL; cur = cur->next)
{
cout << cur->firstName << " " << cur->midIni << " " << cur->lastName << endl;
cout << cur->idNum << endl;
average = (cur->sco1 + cur->sco2 + cur->sco3 + cur->sco4)/4;
cout << cur->sco1 << " " << cur->sco2 << " " << cur->sco3 << " " << cur->sco4 << " " << "average: " << average << endl;
}
}
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