707. 设计链表

做了这么多链表题,还是得要自己会写链表

这题题目已经自带

struct ListNode{
	int val;
	struct ListNode* next;
}

代码:

typedef struct {
    struct ListNode* head;
    int size;
} MyLinkedList;

struct ListNode* ListNodeCreat(int val){
    struct ListNode* node=(struct ListNode*)malloc(sizeof(struct ListNode));
    node->val=val;
    node->next=NULL;
    return node;
}

MyLinkedList* myLinkedListCreate() {
    MyLinkedList* obj=(MyLinkedList *)malloc(sizeof(MyLinkedList));
    obj->head=ListNodeCreat(0);
    obj->size=0;
    return obj;
}

int myLinkedListGet(MyLinkedList* obj, int index) {
    if(index<0||index>=obj->size){
        return -1;
    }
    struct ListNode* cur=obj->head;
    for(int i=0;i<=index;i++){
        cur=cur->next;
    }
    return cur->val;
}

void myLinkedListAddAtHead(MyLinkedList* obj, int val) {
    myLinkedListAddAtIndex(obj,0,val);
}

void myLinkedListAddAtTail(MyLinkedList* obj, int val) {
    myLinkedListAddAtIndex(obj,obj->size,val);
}

void myLinkedListAddAtIndex(MyLinkedList* obj, int index, int val) {
    if(index>obj->size||index<0){
        return;
    }
    obj->size++;
    struct ListNode* pred=obj->head;
    for(int i=0;i<index;i++){
        pred=pred->next;
    }
    struct ListNode* neadd=ListNodeCreat(val);
    neadd->next=pred->next;
    pred->next=neadd;

}

void myLinkedListDeleteAtIndex(MyLinkedList* obj, int index) {
    if(index>=obj->size||index<0){
        return;
    }
    obj->size--;
    struct ListNode* pred=obj->head;
    for(int i=0;i<index;i++){
        pred=pred->next;
    }
    struct ListNode* p=pred->next;
    pred->next=p->next;
    free(p);
}

void myLinkedListFree(MyLinkedList* obj) {
    struct ListNode* cur=NULL,*tmp=NULL;
    for(cur=obj->head;cur;){
        tmp=cur;
        cur=cur->next;
        free(tmp);
    }
    free(obj);
}