Fix 0019

website/content/ChapterFour/0001~0099/0019.Remove-Nth-Node-From-End-of-List.md

@@ -43,8 +43,14 @@ func removeNthFromEnd(head *ListNode, n int) *ListNode {
 	var fast, slow *ListNode
 	fast = head
 	slow = head
+	step := 0
 	for i := 0; i < n; i++ {
+		// n maybe much larger than length of linklist
+		if fast.Next == nil && step != 0 && step < n-1 {
+			return head
+		}
 		fast = fast.Next
+		step++
 	}
 	if fast == nil {
 		head = head.Next