feat: solved 19

Author: fghpdf

src/com/fghpdf/RemoveNthNodeFromEndOfList/Solution.java

@@ -0,0 +1,38 @@
+package com.fghpdf.RemoveNthNodeFromEndOfList;
+
+import com.fghpdf.ListNode;
+
+/**
+ * @author fghpdf
+ * @date 2019/11/15
+ * https://leetcode.com/problems/remove-nth-node-from-end-of-list/
+ * fast and slow pointer
+ * so easy!
+ **/
+public class Solution {
+	public ListNode removeNthFromEnd(ListNode head, int n) {
+		ListNode fast = head;
+		ListNode slow = head;
+
+		if (head == null) {
+			return head;
+		}
+
+		while (fast != null && n != 0) {
+			fast = fast.next;
+			n--;
+		}
+
+		if (fast == null) {
+			return head.next;
+		}
+
+		while (fast.next != null) {
+			fast = fast.next;
+			slow = slow.next;
+		}
+
+		slow.next = slow.next.next;
+		return head;
+	}
+}