middle node ll java

Author: GouravRusiya30

Java/middle-of-the-linked-list.java

@@ -0,0 +1,26 @@
+/**
+ * Definition for singly-linked list.
+ * public class ListNode {
+ *     int val;
+ *     ListNode next;
+ *     ListNode() {}
+ *     ListNode(int val) { this.val = val; }
+ *     ListNode(int val, ListNode next) { this.val = val; this.next = next; }
+ * }
+ */
+class Solution {
+    public ListNode middleNode(ListNode head) {
+        ListNode currentNode = head;
+        
+        ListNode slowPtr = head;
+        ListNode fastPtr = head;
+        
+        while(fastPtr != null && fastPtr.next != null){
+            slowPtr = slowPtr.next; // slow pointer will move 1 node at a time
+            fastPtr = fastPtr.next.next; // fast pointer will move 2 nodes at a time
+        }
+        
+        // at end slow pointer will be pointing to middle node
+        return slowPtr;
+    }
+}