链表的使用

链表

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

初始化

ListNode* InitListNode(int val){ListNode *a ;a = (ListNode *)malloc(sizeof(ListNode));a->next = NULL;a->val = val;return a;
}

插入

//在a后面插入b
void insert(ListNode *a , ListNode *b)
{b->next = a->next;a->next = b;
}

删除

//删除a后面的节点
void del( ListNode * a){if(!a->next) return ;ListNode * p = a->next;ListNode * n = p->next;a->next = n;free(p);
}

访问节点

ListNode *access(ListNode *n,int index){for (int i=0;i<index;i++){if(n->next==NULL) return NULL;n=n->next;}return n;
}

查找

int find(ListNode * node,int target){int index = 0;while(node){if(node->val == target) return index;node = node->next;index++;}reutrn -1;
}

双向链表

typedef struct DoublyListNode{int val;struct DoublyListNode *prev;struct DoublyListNode *next;
} DoublyListNode;

初始化

ListNode *newDoublyListNode(int val){DoublyListNode *node;node = (DoublyListNode *)malloc(sizeof(DoublyListNode));node->prev = NULL;node->next = NULL;node->val = val;
}

析构函数

void delDoublyListNode(DoublyListNode *node){free(node);
}

寻找第i个节点

DoublyListNode GetElem(DoublyListNode * node, int i){for(int j=0;j<i;j++){if(node->next == NULL){printf("i too large!!\n");return NULL;}node = node->next;}return node;
}

插入

//s插入到n的前面
void find(DoublyListNode *n ,DoublyListNode *s){s->next = n->next->prev;s->prev = n;n->next->prev = s;n->next = s;
}

删除

void delete(DoublyListNode *s){s->prev->next = s->next;s->next->prev = s->prev;free(s);
}