You are given the head of a linked list and two integers m and n , write a program to reverse the linked list from position m to n , both inclusive.

Problem Note:

  • It is guaranteed that 1 m n length of linked list
  • Do not use extra space. Do this in-place and in one iteration.

Example 1

Input: 2->4->6->8->10, m = 2, n = 4
Output: 2->8->6->4->10
Explanation: All the elements between position 2 and 4 of the given linked list are reversed.

Example 2

Input: 2->3->7->9->23, m = 1, n = 5
Output: 23->9->7->3->2
Explanation: As m and n are the first and last position of the linked list, the whole linked list is reversed.

Example 3

Input: 10->20->2->5->9->8, m = 3, n = 3
Output: 10->20->2->5->9->8
Explanation: As m = n, there is no change after reversing the linked list from m to n.