Solution Week12:removce-nth-node-from-end-of-list

Author: juhui-jeong

remove-nth-node-from-end-of-list/juhui-jeong.java

@@ -0,0 +1,49 @@
+/* 
+시간 복잡도: O(N)
+공간 복잡도: O(1)
+*/
+class Solution {
+    public ListNode removeNthFromEnd(ListNode head, int n) {
+        ListNode dummy = new ListNode(0);
+        dummy.next = head;
+
+        ListNode fast = dummy;
+        ListNode slow = dummy;
+        
+        for (let i = 0; i <= n; i++) {
+            fast = fast.next;
+        }
+
+        while(fast != null) {
+            fast = fast.next;
+            slow = slow.next;
+        }
+
+        slow.next = slow.next.next;
+
+        return dummy.next;
+    }
+}
+
+/* 
+첫 번째 풀이
+class Solution {
+    public ListNode removeNthFromEnd(ListNode head, int n) {
+        List<ListNode> list = new ArrayList<>();
+        
+        while(head != null) {
+            list.add(head);
+            head = head.next;
+        }
+
+        list.remove(list.size()-n);
+        if (list.isEmpty()) return null;
+
+        for (int i = 0; i < list.size()-1; i++) {
+            list.get(i).next = list.get(i+1);
+        }
+        list.get(list.size()-1).next = null;
+        return list.get(0);
+    }
+}
+*/