add 面试题02-I for Java

Author: EndaLin

lcof/面试题02-I.去除重复节点/Solution.java

@@ -0,0 +1,32 @@
+/**
+ * Definition for singly-linked list.
+ * public class ListNode {
+ *     int val;
+ *     ListNode next;
+ *     ListNode(int x) { val = x; }
+ * }
+ */
+class Solution {
+    public ListNode removeDuplicateNodes(ListNode head) {
+        if (head == null) {
+            return null;
+        }
+        Set<Integer> cache = new HashSet<>();
+        // 初始化参数
+        ListNode pre = head, cur = pre.next;
+        cache.add(head.val);
+
+        while (cur != null) {
+            if (cache.contains(cur.val)) {
+                pre.next = cur.next;
+                cur = pre.next;
+            } else {
+                cache.add(cur.val);
+                pre = cur;
+                cur = cur.next;
+            }
+        }
+        
+        return head;
+    }
+}