建站是什么东西,图片在线设计平台,销售平台是什么意思,重庆网站建设接重庆零臻科技提示#xff1a;文章写完后#xff0c;目录可以自动生成#xff0c;如何生成可参考右边的帮助文档 文章目录 前言一、力扣21. 合并两个有序链表二、力扣86. 分隔链表三、力扣23. 合并 K 个升序链表四、力扣19. 删除链表的倒数第 N 个结点五、力扣876. 链表的中间结点六、力扣… 提示文章写完后目录可以自动生成如何生成可参考右边的帮助文档 文章目录 前言一、力扣21. 合并两个有序链表二、力扣86. 分隔链表三、力扣23. 合并 K 个升序链表四、力扣19. 删除链表的倒数第 N 个结点五、力扣876. 链表的中间结点六、力扣142. 环形链表 II七、力扣160. 相交链表 前言 一、力扣21. 合并两个有序链表
/*** Definition for singly-linked list.* public class ListNode {* int val;* ListNode next;* ListNode() {}* ListNode(int val) { this.val val; }* ListNode(int val, ListNode next) { this.val val; this.next next; }* }*/
class Solution {public ListNode mergeTwoLists(ListNode list1, ListNode list2) {ListNode head new ListNode(-1,null);ListNode p1 list1, p2 list2, r head;while(p1 ! null p2 ! null){if(p1.val p2.val){r.next p1;p1 p1.next;r r.next;}else{r.next p2;p2 p2.next;r r.next;}}if(p1 ! null){r.next p1;}if(p2 ! null){r.next p2;}return head.next;}
}二、力扣86. 分隔链表
/*** Definition for singly-linked list.* public class ListNode {* int val;* ListNode next;* ListNode() {}* ListNode(int val) { this.val val; }* ListNode(int val, ListNode next) { this.val val; this.next next; }* }*/
class Solution {public ListNode partition(ListNode head, int x) {ListNode p1 new ListNode(), p2 new ListNode();ListNode r1 p1, r2 p2, r head;while(r ! null){if(r.val x){ListNode temp r;r r.next;temp.next null;r1.next temp;r1 r1.next;}else{ListNode temp r;r r.next;temp.next null;r2.next temp;r2 r2.next;}}r1.next p2.next;return p1.next;}
}三、力扣23. 合并 K 个升序链表
/*** Definition for singly-linked list.* public class ListNode {* int val;* ListNode next;* ListNode() {}* ListNode(int val) { this.val val; }* ListNode(int val, ListNode next) { this.val val; this.next next; }* }*/
class Solution {public ListNode mergeKLists(ListNode[] lists) {ListNode head new ListNode(), r head;if(lists.length 0){return null;}PriorityQueueListNode pq new PriorityQueue((a,b)-{return a.val - b.val;});for(ListNode node : lists){if(node ! null){pq.add(node);}}while(! pq.isEmpty()){ListNode cur pq.poll();r.next cur;cur cur.next;r r.next;if(cur ! null){pq.add(cur);}}return head.next;}
}四、力扣19. 删除链表的倒数第 N 个结点
/*** Definition for singly-linked list.* public class ListNode {* int val;* ListNode next;* ListNode() {}* ListNode(int val) { this.val val; }* ListNode(int val, ListNode next) { this.val val; this.next next; }* }*/
class Solution {public ListNode removeNthFromEnd(ListNode head, int n) {ListNode res new ListNode(-1,head);ListNode r1 res, r2 res;int len 0;while(len n1){r1 r1.next;len ;}while(r1 ! null){r1 r1.next;r2 r2.next;}r2.next r2.next.next;return res.next;}
}五、力扣876. 链表的中间结点
/*** Definition for singly-linked list.* public class ListNode {* int val;* ListNode next;* ListNode() {}* ListNode(int val) { this.val val; }* ListNode(int val, ListNode next) { this.val val; this.next next; }* }*/
class Solution {public ListNode middleNode(ListNode head) {ListNode p1 head, p2 head;while(p2 ! null p2.next ! null){p2 p2.next;p1 p1.next;if(p2 ! null){p2 p2.next;}else{break;}}return p1;}
}六、力扣142. 环形链表 II
/*** Definition for singly-linked list.* class ListNode {* int val;* ListNode next;* ListNode(int x) {* val x;* next null;* }* }*/
public class Solution {public ListNode detectCycle(ListNode head) {if(head null)return null;ListNode fast head, slow fast;while(fast ! null){slow slow.next;fast fast.next;if(fast null){return null;}else{fast fast.next;if(fast slow){slow head;while(slow ! fast){slow slow.next;fast fast.next;}return fast;}}}return null;}
}七、力扣160. 相交链表
/*** Definition for singly-linked list.* public class ListNode {* int val;* ListNode next;* ListNode(int x) {* val x;* next null;* }* }*/
public class Solution {public ListNode getIntersectionNode(ListNode headA, ListNode headB) {ListNode p1 headA, p2 headB;ListNode max, min;int lenA 0, lenB 0, edge 0;while(p1 ! null){lenA ;p1 p1.next;}while(p2 ! null){lenB ;p2 p2.next;}if(lenA lenB){edge lenA - lenB;max headA;min headB;}else{edge lenB - lenA;max headB;min headA;}while(edge 0){edge --;max max.next; }while(max ! null min ! null){if(max min){return max;}max max.next;min min.next;}return null;}
}
