反转链表

反转整个链表

?

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

/**  * Definition for singly-linked list.  * type ListNode struct {  *     Val int  *     Next *ListNode  * }  */ func reverseList(head *ListNode) *ListNode {     if head==nil||head.Next==nil{         return head     }     last:=reverseList(head.Next)     head.Next.Next=head     head.Next=nil     return last }

　反转链表前N个节点

?

1 2 3 4 5 6 7 8 9 10 11

//反转前n个节点 func reverseN(head *ListNode, n int) *ListNode{     if n==1{         end = head.Next         return head     }     last := reverseN(head.Next,n-1)     head.Next.Next=head     head.Next=end     return last }

　反转链表在区间（left，right）之间的节点

?

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27

/**  * Definition for singly-linked list.  * type ListNode struct {  *     Val int  *     Next *ListNode  * }  */ func reverseBetween(head *ListNode, left int, right int) *ListNode {      if left == 1{          return reverseN(head, right)      }      head.Next = reverseBetween(head.Next,left-1,right-1)      return head } var end *ListNode = nil   //反转前n个节点 func reverseN(head *ListNode, n int) *ListNode{     if n==1{         end = head.Next         return head     }     last := reverseN(head.Next,n-1)     head.Next.Next=head     head.Next=end     return last }