Linkedlist: Remove Nth Node From End of List

removeNthFromEnd.go

/**
 * Definition for singly-linked list.
 * type ListNode struct {
 *     Val int
 *     Next *ListNode
 * }
 */
func removeNthFromEnd(head *ListNode, n int) *ListNode {
    
    dummy := &ListNode{}
    dummy.Next = head
    
    first := head 
    
    var length  int 
    for first != nil { 
        length++
        first = first.Next 
    }
    
    length -= n 
    first = dummy
    // Stop before the node we want to delete
    for length > 0 {       
        first = first.Next
        length--
    }
    
    first.Next = first.Next.Next
    
    return dummy.Next
}