removeDuplicatesFromSortedList.II

Author: zeroliu

src/removeDuplicatesFromSortedList/removeDuplicatesFromSortedList.II.java

@@ -0,0 +1,43 @@
+/**
+ * Definition for singly-linked list.
+ * public class ListNode {
+ *     int val;
+ *     ListNode next;
+ *     ListNode(int x) {
+ *         val = x;
+ *         next = null;
+ *     }
+ * }
+ */
+public class Solution {
+    public ListNode deleteDuplicates(ListNode head) {
+        if (head == null || head.next == null) { return head; }
+        ListNode fakeHead = new ListNode(0);
+        fakeHead.next = head;
+        ListNode b = fakeHead;
+        ListNode f = head;
+        boolean isDuplicated = false;
+        int val = 0;
+        while (f != null) {
+            if (isDuplicated) {
+                if (f.val != val) {
+                    isDuplicated = false;
+                    b.next = f;
+                }
+            }
+            if (!isDuplicated && f.next != null) {
+                if (f.next.val != f.val) {
+                    b = f;
+                } else {
+                    isDuplicated = true;
+                    val = f.val;
+                }
+            }
+            f = f.next;
+        }
+        if (isDuplicated) {
+            b.next = null;
+        }
+        return fakeHead.next;
+    }
+}