diff --git a/Exercise_1.py b/Exercise_1.py
index 532833f5d..1e831fcfb 100644
--- a/Exercise_1.py
+++ b/Exercise_1.py
@@ -2,19 +2,28 @@ class myStack:
   #Please read sample.java file before starting.
   #Kindly include Time and Space complexity at top of each file
      def __init__(self):
-         
+         self.stack = []
      def isEmpty(self):
-         
+      if len(self.stack)==0:
+        return True
+      else:
+        return False
+        
      def push(self, item):
-         
+         self.stack.append(item)
      def pop(self):
-        
+        if len(self.stack)!=0:
+          self.stack.pop()
         
      def peek(self):
-        
+        if len(self.stack)!=0:
+          return self.stack[-1]
+        return []
      def size(self):
+        return len(self.stack)
          
      def show(self):
+        return self.stack
          
 
 s = myStack()
diff --git a/Exercise_2.py b/Exercise_2.py
index b11492215..7c67a4739 100644
--- a/Exercise_2.py
+++ b/Exercise_2.py
@@ -6,10 +6,18 @@ def __init__(self, data):
  
 class Stack:
     def __init__(self):
-        
+        self.pointer = None
     def push(self, data):
-        
+        node = Node(data)
+        node.next = self.pointer
+        self.pointer = node
     def pop(self):
+        if self.pointer is None:
+            print("Stack Empty")
+        else:
+            data = self.pointer.data
+            self.pointer = self.pointer.next
+            return data
         
 a_stack = Stack()
 while True:
diff --git a/Exercise_3.py b/Exercise_3.py
index a5d466b59..2dad2f611 100644
--- a/Exercise_3.py
+++ b/Exercise_3.py
@@ -3,6 +3,8 @@ class ListNode:
     A node in a singly-linked list.
     """
     def __init__(self, data=None, next=None):
+        self.data =data
+        self.next = next
     
 class SinglyLinkedList:
     def __init__(self):
@@ -17,6 +19,17 @@ def append(self, data):
         Insert a new element at the end of the list.
         Takes O(n) time.
         """
+        node = ListNode(data=data)
+        if self.head is None:
+            self.head = node
+            return
+        current = self.head
+        while current.next:
+            current = current.next
+
+        current.next  = node
+
+
         
     def find(self, key):
         """
@@ -24,9 +37,34 @@ def find(self, key):
         `key`. Return the element or `None` if not found.
         Takes O(n) time.
         """
-        
+
+        current = self.head
+        while current.next:
+            if current.data ==key:
+                return current
+            current = current.next
+        return None
     def remove(self, key):
         """
         Remove the first occurrence of `key` in the list.
         Takes O(n) time.
         """
+
+        current = self.head
+        previous = None
+
+        if current is None:
+            print("List Empty")
+            return
+
+        while current:
+            if current.data == key:
+                if previous:
+                    previous.next = current.next
+                else:
+                    self.head = current.next
+                return
+            else:
+                previous = current
+                current = current.next
+