Update deep-copy-with-arbitrary-pointer.md

Author: lightningtgc

coder/linked-lists/deep-copy-with-arbitrary-pointer.md

@@ -1,3 +1,9 @@
 Copy linked list with arbitrary pointer
 
+Q: We are given a linked list where the node has two pointers.
 
+First one is the regular 'next' pointer . 
+
+The second pointer is called 'arbitrary_pointer' that can point to any node in the linked list.
+
+Write code to make a deep copy of the given linked list.