Create FindLoopLength.java

Linked List/Singly Linked List/FindLoopLength.java

@@ -0,0 +1,42 @@
+// Node is defined as:
+// class Node{
+//     int val;
+//     Node next;
+//     Node(){
+//         val =0;
+//         next = null;
+//     }
+//     Node(int x){
+//     	val = x; next = null;
+//     }
+// }
+
+class FindLoopLength{
+
+    static int solve(Node root){
+
+        if (root == null) return -1;
+
+        Node slow = root;
+        Node fast = root;
+
+        while(fast != null && fast.next != null){
+            slow = slow.next;
+            fast = fast.next.next;
+            if(fast == slow){
+                return loopLength(slow);
+            }
+        }
+        return -1;
+    }
+
+    static int loopLength(Node slow){
+        int count = 1;
+        Node ptr = slow.next;
+        while(ptr != slow){
+            count++;
+            ptr = ptr.next;
+        }
+        return count;
+    }
+}