题解 | #牛群的重新排列#

package main
import . "nc_tools"

/*
 * type ListNode struct{
 *   Val int
 *   Next *ListNode
 * }
 */

/**
 * 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 left int整型
 * @param right int整型
 * @return ListNode类
 */
func reverseBetween(head *ListNode, left int, right int) *ListNode {
	// write code here
	if left == right {
		return head
	}
	space := right - left
	dummy := &ListNode{-1, head}
	i, j := dummy, dummy
	for t := 0; t < space; t++ {
		j = j.Next
	}
	var prev *ListNode
	for t := 0; t < left; t++ {
		prev = i
		i = i.Next
		j = j.Next
	}
    next := j.Next
	for i != j {
		temp := i.Next
		i.Next = j.Next
		j.Next = i
		i = temp
	}
    prev.Next = j
    prev = head
    head = next
	return dummy.Next
}