Time: 9 ms (13.40%), Space: 45.3 MB (37.58%) - LeetHub

Author: ahmeddhus

0142-linked-list-cycle-ii/0142-linked-list-cycle-ii.java

@@ -0,0 +1,27 @@
+/**
+ * Definition for singly-linked list.
+ * class ListNode {
+ *     int val;
+ *     ListNode next;
+ *     ListNode(int x) {
+ *         val = x;
+ *         next = null;
+ *     }
+ * }
+ */
+public class Solution {
+    public ListNode detectCycle(ListNode head) {
+        HashSet<ListNode> nodesSet = new HashSet<>();
+
+        while (head != null) {
+            {
+                if (nodesSet.contains(head))
+                    return head;
+
+                nodesSet.add(head);
+                head = head.next;
+            }
+        }
+        return null;
+    }
+}