Thread: A problem with my linked lists test.

It would be nice if someone could help with this problem:
I run this with a file "numb.num" in my E:\ directory that contains:

Code:

123456789

Here's the program:

Code:

#include <iostream.h>
#include <fstream.h>
#include <windows.h>
#include <dos.h>
#include <conio.h>
#include <stdlib.h>


struct node {
 int x;
 node *next;
};

void main() {
 ifstream file1("E:\numb.num");
 int total, a[700], n;
 node *root;
 node *p;
 root->next = NULL;
 for (n = 0;file1.eof();n++) {
  file1 >> a[n];
 }
 for (n = 0;file1.eof();n++) {
  root->x = a[n];
  root->next = new node;
 }
 root->next = NULL;
 p = root;
 for (n = 0;n == NULL || p->next == NULL;n++) {
  total += p->x;
  cout << p->x << " ";
  p = p->next;
 }
 cout << endl << "The total is: " << total << endl;
 p->next = NULL;
 file1.close();
}

Windows crashes the program. And that's about it. I use Visual C++ 6.0 on Windows 98.

Hmmm saw your code

There is a basic problem in the code.

ifstream file1("E:\numb.num");

I think this line shud be changed to

ifstream file1("E:\\numb.num");
Also in this code

node *root;
node *p;
root->next = NULL;
you r assigning NULL to root -> next which is pointing to nowhere. Hence this will give error.

so first do node *root = new node;
and then you will have to do this also
root -> next = new node;
All this you will have to do each time you want to make new node hence you have to change the code everywhere also do it for 'p'

AND ENJOY

Next time

1. Remove unnecessary header files - you limit the number of people who can help you if you include compiler specific header files.

#include <windows.h>
#include <dos.h>
#include <conio.h>

2. remember that main returns int

3. remember that this is the C board, and you posted C++ code.

> for (n = 0;file1.eof();n++) {
Mmm - ok, it might work

> for (n = 0;file1.eof();n++) {
The condition for stopping the second loop is the same as the one which stopped the first loop, so the 2nd loop will never run.