working on 2.4

Author: camilosalazar98

Python/chapter02/2.3 - Delete Middle Node/camilo_solution_2.3.py

@@ -79,17 +79,7 @@ def remove_node(self,data):
         #allow us to unlink the nodes
         prev.next = curr.next
         curr = None
-    """
-    def Kth_to_Last(self,num):
-        counter = 1 # We need to keep track where we are
-        curr = self.head
-        goal = self.size - num# kth to last element
-        while curr is not None:
-            if goal == counter:
-                return curr.data
-            counter+=1
-            curr = curr.next
-    """
+
     def Delete_Middle_Node(self):
         counter = 1
         curr = self.head

Python/chapter02/2.4 - Partition/camilo_solution_2.4.py

@@ -0,0 +1,129 @@
+"""
+Partition: Write code to partition a linked list around a value x, such that all
+ nodes less than x come before all nodes greater than or equal to x. If x is
+ contained within the list, the values of x only need to be after the elements
+ less than x (see below). The partition element x can appear anywhere in the
+ "right partition"; it does not need to appear between the left and right
+ partitions.
+EXAMPLE
+Input: 3 -> 5 -> 8 -> 5 -> 10 -> 2 -> 1[partition=5] Output: 3 -> 1 -> 2 ->
+10 -> 5 -> 5 -> 8
+Hints: #3, #24
+"""
+
+class Node:
+    #Singly link list
+    def __init__(self,data = None):
+        self.data = data
+        self.next = None
+
+class linklist:
+    #linkList class
+    def __init__(self):
+        self.head = None
+        self.size = 0
+
+    def push(self,data):
+        node = Node(data)# create a new node
+
+        if self.head == None: #check to see if the head node is empty
+            self.head = node # If its empty add it to the new node
+            self.size = 1
+            return
+        #if the head of the linklist is filled
+
+        current = self.head
+        while current.next is not None:#Check the current postion is empty
+        #Move to the next line if nothing is there
+            current = current.next
+
+
+        current.next = node #point self.head to a new node
+        self.size+=1
+
+    def lenght(self):
+        #note the count doesn't start at zero
+        cur = self.head
+        counter = 0
+        while cur is not None:
+            counter+=1
+            cur = cur.next
+        print('Linklist len: '+str(counter))
+        return counter
+
+    def printList(self):
+        curr = self.head
+        elem = []
+
+        while(curr != None):
+            elem.append(curr.data)
+            curr = curr.next
+        print(elem)
+    #1->2->3
+    def remove_node(self,data):
+        #1->2->3
+        curr = self.head
+        if curr is not None and curr.data == data:
+            self.head = curr.next
+            curr = None
+        #look for the node that has the data we are looking for
+        while curr is not None:
+            if curr.data == data:
+                break
+            prev = curr
+            curr = curr.next
+
+        #if data isn't found just reutrn
+        if(curr == None):
+            return
+
+        #allow us to unlink the nodes
+        prev.next = curr.next
+        curr = None
+
+    def merge_link(self,NodesA,NodesB):
+
+        while NodesA is not None:
+             Nodec = Node()
+
+
+    def partition(self,num):
+
+        curr= self.head
+        while curr is not None:
+            if(curr.data > num):
+                smallNodes = self.push(curr.data)
+                curr = curr.next
+            else:
+                lagreNodes = self.(curr.data)
+                curr = curr.next
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+llist = linklist()
+llist.push(1)
+llist.push(2)
+llist.push(3)
+llist.push(4)
+llist.push(5)
+llist.push(6)
+llist.printList()
+llist.lenght()
+
+llist.Delete_Middle_Node()# 3 should be removed
+llist.printList()
+llist.lenght()