思路
主要考察队链表结构的熟悉程度
代码
class MyLinkedList {
public:struct LinkedNode {int val;LinkedNode* next;LinkedNode(int val){this->val = val;this->next = nullptr;}};LinkedNode* dummy_head = new LinkedNode(0);int size = 0;MyLinkedList() {dummy_head = new LinkedNode(0);size = 0;}int get(int index) {if(index < 0 || index > size-1){return -1;}LinkedNode* cur = dummy_head->next;while(index--){cur = cur->next;}return cur->val;}void addAtHead(int val) {LinkedNode* cur = new LinkedNode(val);cur->next = dummy_head->next;dummy_head->next = cur;size++;}void addAtTail(int val) {LinkedNode* cur = new LinkedNode(0);cur = dummy_head;while(cur->next != nullptr){cur = cur->next;}LinkedNode* newNode = new LinkedNode(val);cur->next = newNode;size++;}void addAtIndex(int index, int val) {LinkedNode* newNode = new LinkedNode(val);LinkedNode* cur = new LinkedNode(0);cur = dummy_head;if(index > size){return;}else{while(index--){cur = cur->next;}newNode->next = cur->next;cur->next = newNode;size++;}}void deleteAtIndex(int index) {if(index<0 || index > size-1){return;}LinkedNode* cur = new LinkedNode(0);cur = dummy_head;while(index--){cur = cur->next;}cur->next = cur->next->next;size--;}
};
