题解 | #删除链表的节点#
删除链表的节点
https://www.nowcoder.com/practice/f9f78ca89ad643c99701a7142bd59f5d
一、使用虚拟头结点
import java.util.*;
/*
* public class ListNode {
* int val;
* ListNode next = null;
* public ListNode(int val) {
* this.val = val;
* }
* }
*/
public class Solution {
/**
* 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
*
*
* @param head ListNode类
* @param val int整型
* @return ListNode类
*/
public ListNode deleteNode (ListNode head, int val) {
// write code here
ListNode dummy = new ListNode(-1);
dummy.next = head;
ListNode pre = dummy;
ListNode cur = dummy.next;
ListNode tmp = null;
while(cur != null){
tmp = cur.next;
if(cur.val == val){
pre.next = tmp;
break;
}
pre = cur;
cur = tmp;
}
return dummy.next;
}
}
二、不使用虚拟头结点
import java.util.*;
/*
* public class ListNode {
* int val;
* ListNode next = null;
* public ListNode(int val) {
* this.val = val;
* }
* }
*/
public class Solution {
/**
* 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
*
*
* @param head ListNode类
* @param val int整型
* @return ListNode类
*/
public ListNode deleteNode (ListNode head, int val) {
// write code here
ListNode pre = null;
ListNode cur = head;
ListNode tmp = null;
while(cur != null){
tmp = cur.next;
if(cur.val == val){
if(cur == head) return head.next;
pre.next = tmp;
return head;
}
pre = cur;
cur = tmp;
}
return null;
}
}
