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Finalized linked list functions and readme 

The linked lists are finalized, and the readme is updated with a section on linked lists.
This commit is contained in:
Andrew Lalis 2017-05-23 21:11:35 +02:00
parent dad33e0587
commit 306f193312
3 changed files with 106 additions and 31 deletions
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46
README.md
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@ -26,11 +26,7 @@ int is_empty(Stack s);
```
### Description
The stack is probably the most basic storage structure, using the 'first-in,
first-out' approach. To define a stack, the user must first know what type the stack
is, either a primitive type, or a **struct**. To define a stack, you must first define
the **STACK_TYPE** to *int*, *float*, *char*, or whatever type you wish. Then, include
the *handystack* header file.
The stack is probably the most basic storage structure, using the 'first-in, first-out' approach. To define a stack, the user must first know what type the stack is, either a primitive type, or a **struct**. To define a stack, you must first define the **STACK_TYPE** to *int*, *float*, *char*, or whatever type you wish. Then, include the *handystack* header file.
```c
#define STACK_TYPE int
#include "handystack.h"
@ -60,6 +56,46 @@ Where `FUNCTION` is the name of the function.
## Linked List
### Functions
```c
//Creates a new list.
list* new(data, next);
//Recursively frees a list.
void free(List *l);
//Returns the number of elements in a list.
int size(List *l);
//Returns a new list with an item added to the front.
List* add(data, List *l);
//Returns a new list with an item inserted at an index.
List* insert(data, index, List *l);
//Returns the item at an index.
data get(index, List *l);
//Returns a new list with an item at an index removed.
List* remove(index, List *l);
```
### Description
The linked list is a list where each *node* is comprised of a piece of data and a pointer to the next node. The list can have items added, inserted, and removed. To define a list, first define the type of data the list will contain, and then include the *handylist* header file.
```c
#define LIST_TYPE float
#include "handylist.h"
```
To define multiple lists, you must first undefine **LIST_TYPE** like so.
` #undef LIST_TYPE `
Then you simply repeat the instructions above for whatever new list type you would like to make. Just be sure to not define two list types for the same type.
### Example
The following example creates a list of **char** and adds a few to the list, and prints the number added.
```c
#define LIST_TYPE char
#include "handylist.h"
char_list* myList = new_char_list('a', NULL);
myList = add_char_list('b', myList);
myList = add_char_list('c', myList);
myList = insert_char_list('g', 1, myList);
printf("List size: %d\n", size_char_list(myList));
```
[Back to Top](#table-of-contents)
## Heap (Priority Queue)

50
source/handylist.h
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@ -20,10 +20,13 @@ Linked List:
The linked list is a list of items of arbitrary value that are linked via a pointer to the next element, and the last element has a null pointer. The list does not try to maintain any particular order.
*/
/*
LIST_NODE: node for a list.
*/
#define LIST_NODE TEMPLATE(LIST_TYPE,list)
/*
List structure:
List structures:
Each list node will contain a piece of data, which is of an arbitrary type, and a pointer to the next element.
*/
@ -48,7 +51,7 @@ int TEMPLATE(size,LIST_NODE)(LIST_NODE* list){
}
/*
New list:
New list node:
allocates memory for a new list item, and returns it.
*/
LIST_NODE* TEMPLATE(new,LIST_NODE)(LIST_TYPE data, LIST_NODE* next){
@ -60,7 +63,7 @@ LIST_NODE* TEMPLATE(new,LIST_NODE)(LIST_TYPE data, LIST_NODE* next){
}
/*
Free List:
Free List node:
de-allocates memory for a list, and all next items recursively.
*/
void TEMPLATE(free,LIST_NODE)(LIST_NODE* list){
@ -68,26 +71,31 @@ void TEMPLATE(free,LIST_NODE)(LIST_NODE* list){
TEMPLATE(free,LIST_NODE)(list->next);
}
free(list);
list = NULL;
}
/*
Add to the list:
Appends an item to the end of the list.
Appends an item to the front of the list.
*/
void TEMPLATE(add,LIST_NODE)(LIST_TYPE data, LIST_NODE* list){
while (list->next != NULL){
list = list->next;
}
list->next = TEMPLATE(new,LIST_NODE)(data, NULL);
LIST_NODE* TEMPLATE(add,LIST_NODE)(LIST_TYPE data, LIST_NODE* list){
LIST_NODE* newNode = TEMPLATE(new,LIST_NODE)(data,list);
return newNode;
}
/*
Insert List;
Inserts an item at the given index, so that the item can be retreived with the get function at that index.
*/
void TEMPLATE(insert,LIST_NODE)(LIST_TYPE data, int index, LIST_NODE* list){
LIST_NODE* TEMPLATE(insert,LIST_NODE)(LIST_TYPE data, int index, LIST_NODE* list){
if (index == 0){
return TEMPLATE(add,LIST_NODE)(data, list);
}
if (list == NULL){
printf("List is null.\n");
exit(-1);
}
list->next = TEMPLATE(insert,LIST_NODE)(data, index - 1, list->next);
return list;
}
/*
@ -108,4 +116,22 @@ LIST_TYPE TEMPLATE(get,LIST_NODE)(int index, LIST_NODE* list){
return list->data;
}
/*
Remove from list:
Removes an item at an index from the list.
*/
LIST_NODE* TEMPLATE(remove,LIST_NODE)(int index, LIST_NODE* list){
if (list == NULL){
printf("List is null.\n");
exit(-1);
}
if (index == 0){
LIST_NODE* newList = list->next;
free(list);
return newList;
}
list->next = TEMPLATE(remove,LIST_NODE)(index-1, list->next);
return list;
}
#endif

41
test.c
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@ -2,27 +2,40 @@
#include <stdlib.h>
#include <assert.h>
int main(int argc, char* argv[]){
#define STACK_TYPE double
#include "source/handystack.h"
#define LIST_TYPE float
#include "source/handylist.h"
void printList(float_list* list){
int size = size_float_list(list);
for (int i = 0; i < size; i++){
printf("\tIndex: %d, Value: %f\n", i, get_float_list(i, list));
}
for (int i = 0; i < 20; i++){
printf("-");
}
printf("\n");
}
int main(int argc, char* argv[]){
double_stack s = new_double_stack();
push_double_stack(42.5, &s);
print_double_stack(s);
#ifdef LIST_TYPE
#undef LIST_TYPE
#endif
#define LIST_TYPE float
#include "source/handylist.h"
float_list* l = new_float_list(5.0, NULL);
add_float_list(6.0, l);
add_float_list(7.0, l);
add_float_list(8.0, l);
printf("%d\n", size_float_list(l));
printf("%f\n", get_float_list(3, l));
insert_float_list(15.05, 2, l);
printf("%f\n", get_float_list(1, l));
l = add_float_list(6.0, l);
l = add_float_list(7.0, l);
l = add_float_list(8.0, l);
printList(l);
l = insert_float_list(15.5525, 2, l);
l = insert_float_list(25, 0, l);
printList(l);
l = remove_float_list(2, l);
printList(l);
free_float_list(l);
}