Create 0707-design-linked-list.c

Author: Ritesh7766

c/0707-design-linked-list.c

@@ -0,0 +1,130 @@
+typedef struct Node {
+    struct Node* next;
+    struct Node* prev;
+    int val;
+} Node;
+
+typedef struct {
+    Node* head;
+    Node* tail;
+    int length;
+} MyLinkedList;
+
+Node* createNode(int val) {
+    Node* new_node = (Node*)malloc(sizeof(Node) );
+    new_node->next = NULL;
+    new_node->prev = NULL;
+    new_node->val = val;
+    return new_node;
+}
+
+MyLinkedList* myLinkedListCreate() {
+    MyLinkedList* list = (MyLinkedList*)malloc(sizeof(MyLinkedList) );
+    list->head = createNode(-1);
+    list->tail = list->head;
+    list->length = 0;
+    return list;
+}
+
+Node* traverseList(MyLinkedList* obj, int index) {
+    if (index < 0 || index >= obj->length)
+        return NULL;
+    Node* trev = obj->head;
+    while (index >= 0) {
+        trev = trev->next;
+        index -= 1;
+    }
+    return trev; 
+}
+
+int myLinkedListGet(MyLinkedList* obj, int index) {
+    Node *node = traverseList(obj, index);
+    if (node != NULL)
+        return node->val;
+    return -1;
+}
+
+void myLinkedListAddAtHead(MyLinkedList* obj, int val) {
+    Node* new_node = createNode(val);
+    new_node->next = obj->head->next;
+    new_node->prev = obj->head;
+    obj->head->next = new_node;
+    if (new_node->next != NULL)
+        new_node->next->prev = new_node;
+    else
+        obj->tail = new_node;
+    obj->length += 1;
+    return;
+}
+
+void myLinkedListAddAtTail(MyLinkedList* obj, int val) {
+    Node* new_node = createNode(val);
+    obj->tail->next = new_node;
+    new_node->prev = obj->tail;
+    obj->tail = obj->tail->next;
+    obj->length += 1;
+    return;
+}
+
+void myLinkedListAddAtIndex(MyLinkedList* obj, int index, int val) {
+    if (index == 0) {
+        myLinkedListAddAtHead(obj, val);
+        return;
+    }
+    else if (index == obj->length) {
+        myLinkedListAddAtTail(obj, val);
+        return;
+    }
+    Node* prev_node = traverseList(obj, index - 1);
+    if (prev_node == NULL)
+        return;
+    Node* new_node = createNode(val);
+    new_node->next = prev_node->next;
+    new_node->prev = prev_node;
+    prev_node->next = new_node;
+    if (new_node->next != NULL)
+        new_node->next->prev = new_node;
+    obj->length += 1;
+    return;
+}
+
+void myLinkedListDeleteAtIndex(MyLinkedList* obj, int index) {
+    Node *node = traverseList(obj, index);
+    if (node == NULL)
+        return;
+    Node *temp = node;
+    node->prev->next = node->next;
+    if (node->next != NULL)
+        node->next->prev = node->prev;
+    else
+        obj->tail = node->prev; 
+    obj->length -= 1;
+    free(temp);
+    return;
+}
+
+void myLinkedListFree(MyLinkedList* obj) {
+    Node *prev = NULL, *cur = obj->head;
+    while (cur != NULL) {
+        prev = cur;
+        cur = cur->next;
+        free(prev);
+    }
+    free(obj);
+}
+
+/**
+ * Your MyLinkedList struct will be instantiated and called as such:
+ * MyLinkedList* obj = myLinkedListCreate();
+ * int param_1 = myLinkedListGet(obj, index);
+ 
+ * myLinkedListAddAtHead(obj, val);
+ 
+ * myLinkedListAddAtTail(obj, val);
+ 
+ * myLinkedListAddAtIndex(obj, index, val);
+ 
+ * myLinkedListDeleteAtIndex(obj, index);
+ 
+ * myLinkedListFree(obj);
+*/