diff --git a/src/advance/crackingCodingInterview/ListNode.java b/src/advance/crackingCodingInterview/ListNode.java
new file mode 100644
index 0000000..a9120db
--- /dev/null
+++ b/src/advance/crackingCodingInterview/ListNode.java
@@ -0,0 +1,2 @@
+package advance.crackingCodingInterview;public class ListNode {
+}
diff --git a/src/advance/crackingCodingInterview/Tests.java b/src/advance/crackingCodingInterview/Tests.java
new file mode 100644
index 0000000..64641b2
--- /dev/null
+++ b/src/advance/crackingCodingInterview/Tests.java
@@ -0,0 +1,2 @@
+package advance.crackingCodingInterview;public class Tests {
+}
diff --git a/src/advance/crackingCodingInterview/linkedList/general/DeleteDuplicates.java b/src/advance/crackingCodingInterview/linkedList/general/DeleteDuplicates.java
new file mode 100644
index 0000000..0a06c52
--- /dev/null
+++ b/src/advance/crackingCodingInterview/linkedList/general/DeleteDuplicates.java
@@ -0,0 +1,26 @@
+package advance.crackingCodingInterview.linkedList.palindromes;
+
+import advance.crackingCodingInterview.ListNode;
+
+import java.util.HashSet;
+import java.util.Set;
+
+public class DeleteDuplicates {
+
+    // TC and SC is: O(n)
+    public void deleteDup(ListNode node) {
+        Set<Integer> set=new HashSet<>();
+        ListNode previousNode=null;
+
+        while (node != null){
+            if (set.contains(node.data)){
+                previousNode.next = node.next;
+            }
+            else {
+                set.add(node.data);
+                previousNode = node;
+            }
+            node = node.next;
+        }
+    }
+}
diff --git a/src/advance/crackingCodingInterview/linkedList/general/DeleteMiddle.java b/src/advance/crackingCodingInterview/linkedList/general/DeleteMiddle.java
new file mode 100644
index 0000000..793646f
--- /dev/null
+++ b/src/advance/crackingCodingInterview/linkedList/general/DeleteMiddle.java
@@ -0,0 +1,2 @@
+package advance.crackingCodingInterview.linkedList.general;public class DeleteMiddle {
+}
diff --git a/src/advance/crackingCodingInterview/linkedList/general/DetectLoopInLinkedList.java b/src/advance/crackingCodingInterview/linkedList/general/DetectLoopInLinkedList.java
new file mode 100644
index 0000000..fe70c4f
--- /dev/null
+++ b/src/advance/crackingCodingInterview/linkedList/general/DetectLoopInLinkedList.java
@@ -0,0 +1,2 @@
+package advance.crackingCodingInterview.linkedList.general;public class DetectLoopInLinkedList {
+}
diff --git a/src/advance/crackingCodingInterview/linkedList/general/KthToLast.java b/src/advance/crackingCodingInterview/linkedList/general/KthToLast.java
new file mode 100644
index 0000000..dc564d0
--- /dev/null
+++ b/src/advance/crackingCodingInterview/linkedList/general/KthToLast.java
@@ -0,0 +1,2 @@
+package advance.crackingCodingInterview.linkedList.general;public class KthToLast {
+}
diff --git a/src/advance/crackingCodingInterview/linkedList/palindromes/PalindromeRC.java b/src/advance/crackingCodingInterview/linkedList/palindromes/PalindromeRC.java
new file mode 100644
index 0000000..a12fb19
--- /dev/null
+++ b/src/advance/crackingCodingInterview/linkedList/palindromes/PalindromeRC.java
@@ -0,0 +1,27 @@
+package advance.crackingCodingInterview;
+// Check if the linked list is a palindrome
+
+public class Palindrome {
+
+
+    public boolean isPalindrome(ListNode head) {
+        return false;
+    }
+
+    static boolean isEqual(ListNode firstNode, ListNode secondNode){
+        while (firstNode != null && secondNode != null){
+            if (firstNode.data != secondNode.data){
+                return false;
+            }
+            firstNode = firstNode.next;
+            secondNode  = secondNode.next;
+        }
+        return firstNode == null && secondNode == null;
+    }
+
+    public ListNode reverseAndClone(ListNode node){
+        
+    }
+
+
+}
diff --git a/src/advance/crackingCodingInterview/linkedList/palindromes/PalindromeStack.java b/src/advance/crackingCodingInterview/linkedList/palindromes/PalindromeStack.java
new file mode 100644
index 0000000..aa0576e
--- /dev/null
+++ b/src/advance/crackingCodingInterview/linkedList/palindromes/PalindromeStack.java
@@ -0,0 +1,2 @@
+package advance.crackingCodingInterview.linkedList.palindromes;public class PalindromeStack {
+}
diff --git a/src/advance/linkedlist/LFUCache.java b/src/advance/linkedlist/LFUCache.java
new file mode 100644
index 0000000..4bcede5
--- /dev/null
+++ b/src/advance/linkedlist/LFUCache.java
@@ -0,0 +1,2 @@
+package advance.linkedlist;public class LFUCache {
+}