I am creating linked list of memory blocks. Allocate a block of 512 bytes and insert into the first node of list. then Allocate a 2nd block of same size and add to the list. now free each block from the list.
View 14 RepliesI'm trying to write a function that takes two linked lists and creates a third one with only the common elements.
It assumes the first list (the caller) has no dups, but it doesn't seem to be working. The program doesn't crash, it just hangs when it is supposed to display L3 (the third list)..everything else runs and is displayed fine.
template <typename T>
LList <T> LList <T>:: common (LList <T> &B)//common fct
{
Node <T> *hunter1 = Head;
[Code]......
I've been making a circular linked list and I'm trying to assign each list a "name" and its next "link" but when I run my code it crashes.
Soldier *Head;
Head = NULL;
string names[] = {"Arman","Bogut","Castro","Damascus","Elene"};
for (int i = 0; i < 5; ++i) {
[Code] .....
How would I go about creating a tree like structure using linked lists, I am thinking of making a rubix cube solver program, what I want to do create nodes that each do one operation like turn left, right, up, down but I dont know how to go about starting this.
View 2 Replies View RelatedCode:
#include <stdlib.h>
#include <stdio.h>
typedef struct characterNode {
char c;
characterNode *prev;
characterNode *next;
} CharacterNode;
[Code]...
What's wrong with this? People told me that casting malloc was bad, but I don't understand what struct cn *temp is doing.
Also, could I create something like:
Code: typedef CharacterNode *CharacterNodePtr To be a pointer to my struct type? Why would that be beneficial?
I need to create a templated doubly linked list, with an iterator class within the list class. This program is to function just like the STL list class but I only need to implement functions that I am using, My trouble is I am kind of clueless on the iterator part and the fact that the list is templated is giving me syntax grief. I have pasted the code I have done so far.
1. On the syntax implementing the list and iterator functions outside of the class
2. I am not sure when to deference the iterator in the functions, but think I have it right so far
3. For the reverse function can I copy the list into a new list in reverse then re add them to the original list overwriting the same values? I have the code I have so far there
4. For the iterator erase function, I am not sure if I am deleting the node correctly.
5. I am not sure if I need template <typename T> above the iterator functions. Does the iterator class need to be a template? Right now it is not.
// Templated doubly linked list class
#include <iostream>
using namespace std;
template <typename T>
class list {
private:
Node *head;
Node *tail;
[Code] ....
I am having issues freeing memory that I allocated when adding a node to a doubly linked list. I have tried adding free() at the end of the remove function from the list with no luck. I have tried using all sorts of temporary nodes and dummy nodes to free without losing node information. Have tried storing current node, moving to next one, then freeing the old current one, without luck. Everytime I try to free a node it destroys the list. It loses important node information and can no longer operate properly and I am met with all sorts of memory crashes. I will post my add and delete nodes functions here:
/**
* Adds a node to a given list
*
* @param q pointer a a list
* @param node pointer to the node to be added
*/
void list_add(list *q, path *node){
path *pn;
if(!(pn = (path*)malloc(sizeof(*pn)))){
perror("malloc");
exit(1);
[Code] ....
Those free's at the end are to get rid of nodes I malloced in find_path. This find_path works really well when run once lol. It finds shortest path and prints it no problem, but doing it over and over again will be problematic as it is leaking almost every bit of memory it uses />.
So in short, how to free an allocated node when I remove it from a list while still being able to use it? I have tried moving the remove function to different locations like the end of the file and still no luck. I even tried allocating a new current_node each iteration of while loop, using it, then freeing it at the end of the while loop and took out the allocation in the list_add() function. This didn't work either />. How to stop the leakage.
I've been working on this program and am finished with what I want it to accomplish. But the last step I'd like to take is to delete the linked list and free all the memory. When I free the memory the way I am right now, the program breaks. I'm not sure how I should go about freeing and setting things to NULL.
Code:
typedef struct node {
char* value;
struct node* next;
} LinkedList;
//function prototypes
void llAdd(LinkedList** ll, char* value);
[Code] .....
In the program I'm writing, I'm creating a linked list of students with individual data read from a file. At the moment, I have written two functions to accomplish this; one that creates a student node and fills it from a line file, and a second that calls on the first to create a linked list. It seems to work fine except for one thing; It seems that EOF is being reached first, but the function continues on anyways? Here is my code so far...
Code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct student
// Declaring student structure globally.
[Code] .....
And here is what the input file would look like...
Thui Bhu, 100, 90, 80, 100, 89, 99, 88
Ariana B. Smith, 90, 90, 100, 100, 99, 100, 95
Emily Gonzales, 100, 90, 100, 70, 78, 78, 80
Jennifer L, 80, 90, 90, 100, 89, 99, 85
Maria Jones, 65, 72, 77, 68, 62, 70, 65
Bill Gates, 60, 54, 38, 62, 65, 60, 50
Escobar Morris, 83, 77, 88, 76, 79, 72, 76
Anne Latner, 80, 80, 85, 95, 90, 95, 98
John Doe, 45, 87, 88, 89, 67, 96, 79
And here is what the output is...
EOF
EOF in create_record
Thui Bhu: 100 90 80 100 89 99 88
Ariana B. Smith: 90 90 100 100 99 100 95
Emily Gonzales: 100 90 100 70 78 78 80
Jennifer L: 80 90 90 100 89 99 85
Maria Jones: 65 72 77 68 62 70 65
Bill Gates: 60 54 38 62 65 60 50
Escobar Morris: 83 77 88 76 79 72 76
Anne Latner: 80 80 85 95 90 95 98
John Doe: 45 87 88 89 67 96 79
Press any key to continue . . .
Well, basically, what I've been doing was creating a class that would implement the concept of Double Linked List, but that would behave like a queue ( the STL implementation is deque, or Double Ended Queue ).
The problem occured when I have been trying to generalize the class using templates. I mean, why use only integers ? Why not double or char or what not ?
Worked perfectly before including all the template stuff..
// Source.cpp <=> Main.cpp
#include <iostream>
#include "DList.h"
using namespace std;
int main(void) {
DList<int> *list;
list = new DList<int>();
[Code] .....
The errors returned by the compiler:
Error1error C2955: 'Node' : use of class template requires template argument listc:usersjumperdesktopc++ otherdouble linked listdouble linked listdlist.h6
Error2error C2955: 'Node' : use of class template requires template argument listc:usersjumperdesktopc++ otherdouble linked listdouble linked listdlist.h6
I've written this class and struct to create a singly linked list. The data is stored in the binary file which I've opened and read. I'm trying to load said data into a class type array. The errors I'm getting are "incompatible types in assignment of 'StatehoodInfo' to char[3]" Lines 130-134 is what I was working on.
#include <iostream>
#include <iomanip>
#include <fstream>
#include <sstream>
#include <string>
#include <cstring> //For char[] string functions
[Code] .....
I'm trying to keep track of the size of blocks of memory that a pointer points to. No matter what I do, this code below always outputs the integer 8.
If I change 1000 to 5, I still get 8. If I change it to 0, I get 8... If I change it to -1, I get 8. If I change int *a to double *a, I get 8. If I take away the & symbol, I get 8. If I use *& instead, I get 8.
Why? I want it to output 1000. If I change that to 500, I want it to output 500.
int *a;
a = malloc(1000 * sizeof(int));
int j = sizeof(&a);
printf("%d", j);
I want to build my skills where I can allocate, inspect and change memory sizes.
I have a linked list comprised of chars like so...
Code:
node1 - "p"
node2 - "o"
node3 - "p"
I need a function that will take in three perameters...node *replaceChar(node *head, char key, char *str)Stipulations of this function. head is the head of the list, 'key' and 'str' are guaranteed to contain alphanumeric characters only (A-Z, a-z, and 0-9). str can range from 1 to 1023 characters (inclusively). So if I call this function with these perameters..
Code:
node *head == /*the head of the list to be examined*/
char key == "p"char *str == "dog"The new list will look like this...
node1 - 'd'
node2 - 'o'
node3 - 'g'
node4 - 'o'
node5 - 'd'
node6 - 'o'
node7 - 'g'
All instances of 'p' were replaced with 'dog' I have a toString function which takes in a string and converts it to a linked list and returns the head. So assume that you can call the function on str = "dog" so...
Code:
toString(str) == /*this will return the head to the list made from the str*/
If it's unclear what my question is...I am stumped on how to write the replaceChar function the one that takes in three perameters..
Code:
// Write a function called insertEntry() to insert a new entry into a linked list.
Have the procedure take as arguments a pointer to the list entry to be inserted (of type struct entry as defined in this chapter), and a pointer to an element in the list after which the new entry is to be inserted.
// The function dveloped in exercise 2 only inserts an element after an existing element in the list, thereby prenting you from inserting a new entry at the front of the list.
(Hint: Think about setting up a special structure to point to the beginning of the list.)
#include <stdio.h
struct entry1 {
int value;
struct entry1 *next;
};
[code]...
This is a working version of the exercise, but I don't think I'm doing what's asked. I was able to add an element to the beginning of the list using an if statement, not creating a special structure that points to the beginning of the list. How would I go about creating a special structure that points to the beginning of the list to add a new element at the beginning of the list?
I am struggling to finish up my game of War. There are a few problems I have ran in to. My shuffle function seems to work fine. I believe my problem lies within my game rules. When I run my code, the game usually plays all the way through but almost always ends in 'War'. I am struggling to get the game to restart after running once. I am not sure how to clear the list and start over.
Code:
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <time.h>
#include <Windows.h>
[Code] ....
I'm working on a linked list and was wondering how this looks to everybody else for a deleteList function.
void deleteList(Node* head)
{
Node* iterator = head;
while (iterator != 0)
[code].....
Having some frustrating issues trying to free memory from a dynamically allocated array of pointers to linked lists. I think the problem is in how I initialize the pointers to NULL. Is there a more elegant way to have the program recognize that the list is empty so it knows to create a head node for the linked list in the function 'add_end_stub_to_array'?
I ran the code through Valgrind and it says that memory is definitely lost from this array.
This is the structure definition.
Code: struct stub_edge {
int loc_id;
int anim_type;
int mkt;
struct stub_edge *next_node;
};
Here is the code snippet from main allocating and deallocating memory to the array.
Code:
struct stub_edge **stub_list = (struct stub_edge **)malloc( sizeof(struct stub_edge *) * 12);
for (i = 0; i < 12; i++)
{
stub_list[i] = (struct stub_edge *)malloc(sizeof(struct stub_edge));
stub_list[i] = NULL;
}
stub_list = add_end_stub_to_array(end_stubs, stub_list);
destroy_end_stub_array(stub_list);
Here the function for adding nodes to the lists by reading through a dynamically allocated 2D array. (The end_stubs array is ordered by month and each linked list represents events occuring within the month).
Code:
struct stub_edge **add_end_stub_to_array(int **end_stubs, struct stub_edge **list)
{
long int i = 0;
int mon = 0;
struct stub_edge *current_node1;
struct stub_edge *new_node1;
int break1 = 0;
while(i < num_edges && break1 == 0 && mon < 12)
[Code]...
Here is the function for freeing memory from the list.
Code:
void destroy_end_stub_array(struct stub_edge **list)
{
if(list != NULL)
{
int mon = 0;
struct stub_edge *current_node1;
struct stub_edge *new_node1;
for(mon = 0; mon < 12; mon++)
[Code]...
Creating the methods for class List
main.cpp Code: #include "List.h"
int main( )
{
List la; // create list la
la.push_front( "mom" );
la.push_back( "please" );
la.push_back( "send" );
la.push_back( "money" );
la.push_front( "hi" );
cout << "
la contains:
" << la << '
[code]...
I would like to have a List with Lists. (every list with have strings ints and i would like to be able to have all the lists in a array) is this approach too expensive and i will have problem with the memory or something? is it better if i have a list with the names of the lists and access them that way?
In order to give a better understanding of what i need this is what im trying to do but throws errors:
public List<MusicItem> Theme1 { get; set; }
public List<List<MusicItem>> AllThemes { get; set; }
AllThemes = new List<List<MusicItem>> {
Theme1 = new List<MusicItem> {
[Code] .....
Im trying to do something like this:
private List<Calm> calm = null;
private List<Horror> horror = null;
private List<Battle> battle = null;
[Code].....
I want with lists[0][0].Name to get the Name variable from the first item of the list calm, but this doesnt working, is there any other way to do it?
I have to create a list of words and then when one is repeated the program has to show with a message.
Code:
#include <vcl.h>
#include <iostream.h>
#include <conio.h>
#include <string.h>
#pragma hdrstop
[Code] ....
I wrote this program to create a list of medical resources and their attributes, a task I have been performing repeatedly lately. I'm still fairly new to C++, so I thought to create a structure "Resource", and then an array of those structures "city[300]". My problem is that the input doesn't seem to be happening: the program runs, but when it prints to screen/writes to the file at the end, all the shows is:
Resource Type:
Name:
Address:
Phone:
Website:
for every resource that was input. All the fields are blank.
#include <iostream>
#include <fstream>
#include <string>
using namespace std;
struct Resource {
string typeID;
string name;
[Code] ....
I need to make the functions using these function prototypes. I am mainly having problems with GetFirst() and SwapData() but how to do it..
Header File with Prototypes
Code:
#ifndef LINKEDLIST_H
#define LINKEDLIST_H
/**
* @file
* This file provided a doubly-linked list implementation capable of storing any arbitrary data.
* The list implementation relies on a chain metaphor: a list is merely a sequence of links
* (ListItems) and there is no separate construct to represent the entire list, each ListItem in it
[Code]....
I read an article on linked list here: C Linked List Data Structure Explained with an Example C Program
Code:
struct test_struct* search_in_list(int val, struct test_struct **prev)
{
struct test_struct *ptr = head;
struct test_struct *tmp = NULL;
bool found = false;
}
[code].....
What is "if(prev)"? Wouldn't "prev" always have the same value? Secondly, if tmp is NULL (which will be the case when the loop if(ptr->val == val) finds a match the first time it is run), is *prev assigned a NULL?
I'm having a small issue here with my linked list.I built a linked list with strings and it worked perfectly.Now since i'm using strtok() to separate the string.for now here's what i've got:
Code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
typedef struct dict_word *word;
typedef struct node *Node;
typedef struct double_linked_list *DLL;
}
[code]....
I have the codes for the functions: "Given the functions that we have discussed and defined in the class and the code that we have created, create the code for the Delete Node function and the Search function. Create an application that will incorporate all the functions that we have discussed and the new ones that you need to create. The application should allow the linked list to be built initially from a text file. The application should then allow for the user select an operation to perform. The acceptable operations are
- to search for an item
- to delete an item
- to enter a new item
- to exit the application
After the initial build and loading of data from the textfile, the application should print a listing of each item in the list and the node that it is located in. after a delete or insert, the application should display an output of the list again showing each item in the list and the node that it resides in.
The data item for this problem will be the inventory structure that we created in class and the data is in the inventory file that you already have downloaded."