diff options
Diffstat (limited to 'sem3/algo/mm2/linked/llist.c')
-rw-r--r-- | sem3/algo/mm2/linked/llist.c | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/sem3/algo/mm2/linked/llist.c b/sem3/algo/mm2/linked/llist.c new file mode 100644 index 0000000..41ab892 --- /dev/null +++ b/sem3/algo/mm2/linked/llist.c @@ -0,0 +1,89 @@ +#include "llist.h" + +#include <string.h> +#include <stdio.h> + + +#define OUT_OFF_BOUNDS 2 + +void llist_init(llist_t *list) { + /* Zero out structure */ + list->head = list->root = NULL; + + list->len = 0; + +} + +void llist_append(llist_t *list, int val) { + /* Insert node after HEAD */ + list->head = node_insert(list->head, val); + + /* Check if was list is empty */ + if( list->len == 0 ) { + /* Set root */ + list->root = list->head; + } + + /* Increase count */ + list->len++; +} + +node_t *llist_get_node(llist_t *list, unsigned int index) { + /* Check if we have it */ + if( index >= list->len ) { + return NULL; + } + + /* Find the best way to go down the list */ + int direc = index > (list->len / 2) ? -1 : 1; + + /* Setup start location */ + int pos = direc > 0 ? 0 : list->len-1; + node_t *node = direc > 0 ? list->root : list->head; + + /* Go to index */ + while( pos != index ) { + /* TODO kinda risky, we trust our math and len */ + node = direc > 0 ? node->next : node->prev; + + pos += direc; + } + + return node; +} + +int llist_get(llist_t *list, unsigned int index) { + /* Get node */ + node_t *node = llist_get_node(list, index); + if( node == NULL ) { + /* Yes i know this is stupid */ + return -1; + } + + /* Return value */ + return node->val; +} + + +int llist_pop(llist_t *list, unsigned int index) { + /* Get node */ + node_t *node = llist_get_node(list, index); + if( node == NULL ) { + /* Yes i know this is stupid */ + return -1; + } + + /* Update root and head if we delete it */ + if( node == list->root ) { + list->root = node->next; + } + if( node == list->head ) { + list->head = node->prev; + } + + /* Keep len up to date */ + list->len--; + + /* Delete stuff */ + return node_pop(node); +} |