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Commit bf2fef3

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Final commit. Book complete.I'm So happygit add *
1 parent c6b5981 commit bf2fef3

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6 files changed

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6 files changed

+493
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lines changed

‎BST.py

Lines changed: 223 additions & 0 deletions
Original file line numberDiff line numberDiff line change
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class TreeNode:
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'''A node for the Binary Search Tree '''
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def __init__(self,key,val,left=None,right=None,parent=None):
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self.key = key
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self.payload = val
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self.leftChild = left
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self.rightChild = right
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self.parent = parent
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def hasLeftChild(self):
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return self.leftChild
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def hasRightChild(self):
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return self.rightChild
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def isLeftChild(self):
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return self.parten and self.parent.leftChild == self
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def isRightChild(self):
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return self.parent and self.parent.rightChild == self
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def isRoot(self):
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return not self.parent
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def isLeaf(self):
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return not (rightChild or self.leftChild)
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def hasAnyChildren(self):
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return self.rightChild or self.leftChild
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def hasBothChildren(self):
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return self.rightChild and self.leftChild
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def replaceNodeData(self,key,value,lc,rc):
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self.key = key
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self.payload = value
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self.leftChild = lc
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self.rightChild = rc
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if self.hasLeftChild():
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self.leftChild.parent = self
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if self.hasRightChild():
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self.rightChild.parent = self
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def findSuccessor(self):
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succ = None
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if self.hasRightChild():
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succ = self.rightChild.findMin()
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else:
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if self.parent:
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if self.isLeftChild():
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succ = self.parent
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else:
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self.parent.rightChild = None
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succ = self.parent.findSuccessor()
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self.parent.rightChild =self
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return succ
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def findMin(self):
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current = self
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while current.hasLeftChild():
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current = current.leftChild
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return current
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def spliceOut(self):
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if self.isLeaf():
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if self.isLeftChild():
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self.parent.leftChild = None
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else:
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self.parent.rightChild = None
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elif self.hasAnyChildren():
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if self.hasLeftChild():
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if self.isLeftChild():
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self.parent.leftChild = self.leftChild
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else:
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self.parent.rightChild = self.leftChild
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self.leftChild.parent = self.parent
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else:
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if self.isLeftChild():
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self.parent.rightChild = self.rightChild
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else:
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self.parent.rightChild = self.rightChild
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self.rightChild.parent = self.parent
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def __iter__(self):
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if self:
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if self.hasLeftChild():
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for elem in self.leftChild:
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yield elem
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yield self.key
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if self.hasRightChild():
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for elm in self.rightChild:
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yield elem
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class BinarySearchTree:
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def __init__(self):
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self.root = None
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self.size = 0
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def length(self):
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return self.size
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def __len__(self):
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return self.size
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def __iter__(self):
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return self.root.__iter__()
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def put(self,key,val):
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if self.root:
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self._put(key,val,self.root)
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else:
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self.root = TreeNode(key,val)
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self.size = self.size + 1
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def _put(self,key,val,currentNode):
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if key < currentNode.key:
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if currentNode.hasLeftChild():
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self._put(key,val,currentNode.leftChild)
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else:
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currentNode.leftChild = TreeNode(key,val,parent=currentNode)
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elif key == currentNode.key:
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currentNode.payload = val
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else:
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if currentNode.hasRightChild():
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self._put(key,val,currentNode.rightChild)
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else:
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currentNode.rightChild = TreeNode(key,val,parent=currentNode)
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def __setitem__(self,k,v):
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self.put(k,v)
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def get(self,key):
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if self.root:
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res = self._get(key,self.root)
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if res:
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return res.payload
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else:
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return None
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else:
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return None
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def _get(self,key,currentNode):
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if not currentNode:
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return None
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elif currentNode.key == key:
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return currentNode
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elif key < currentNode.key:
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return self._get(key,currentNode.leftChild)
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else:
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return self._get(key,currentNode.rightChild)
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def __getitem__(self,key):
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return self.get(key)
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def __contains__(self,key):
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if self._get(key,self.root):
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return True
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else:
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return False
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def delete(self,key):
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if self.size > 1:
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nodeToRemove = self._get(key,self.root)
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if nodeToRemove:
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self.remove(nodeToRemove)
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self.size = self.size-1
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else:
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raise KeyError('Error, key not in tree')
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elif self.size == 1 and self.root.key == key:
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self.root = None
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self.size = self.size - 1
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else:
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raise KeyError('Error, key not in tree')
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def __delitem__(self,key):
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self.delete(key)
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def remove(self,currentNode):
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if currentNode.isLeaf(): #leaf
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if currentNode == currentNode.parent.leftChild:
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currentNode.parent.leftChild = None
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else:
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currentNode.parent.rightChild= None
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elif currentNode.hasBothChildren(): #interior
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succ = currentNode.findSuccessor()
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succ.spliceOut()
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currentNode.key = succ.key
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currentNode.payload = succ.payload
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else: #this node has one child
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if currentNode.hasLeftChild():
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if currentNode.isLeftChild():
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currentNode.leftChild.parent = currentNode.parent
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currentNode.parent.leftChild = currentNode.leftChild
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elif currentNode.isRightChild():
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currentNode.leftChild.parent = currentNode.parent
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currentNode.parent.rightChild = currentNode.leftChild
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else:
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currentNode.replaceNodeData(currentNode.leftChild.key,
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currentNode.leftChild.payload,
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currentNode.leftChild.leftChild,
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currentNode.leftChild.rightChild)
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else:
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if currentNode.isLeftChild():
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currentNode.rightChild.parent = currentNode.parent
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currentNode.parent.leftChild = currentNode.rightChild
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elif currentNode.isRightChild():
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currentNode.rightChild.parent = currentNode.parent
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currentNode.parent.rightChild = currentNode.rightChild
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else:
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currentNode.replaceNodeData(currentNode.rightChild.key,
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currentNode.rightChild.payload,
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currentNode.rightChild.leftChild,
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currentNode.rightChild.rightChild)
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mytree = BinarySearchTree()
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mytree[3]="red"
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mytree[4]="blue"
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mytree[6]="yellow"
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mytree[2]="at"
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print(mytree[6])
223+
print(mytree[2])

‎BinaryHeap.py

Lines changed: 59 additions & 0 deletions
Original file line numberDiff line numberDiff line change
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class BinHeap:
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def __init__(self):
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self.heap_list = [0]
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self.current_size = 0
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def perc_up(self, i):
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while i//2 > 0:
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if self.heap_list[i] < self.heap_list [i //2]:
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tmp = self.heap_list[i // 2]
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self.heap_list[i // 2] = self.heap_list[i]
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self.heap_list[i] = tmp
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i = i // 2
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def insert(self, k):
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self.heap_list.append(k)
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self.current_size += 1
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self.perc_up(self.current_size)
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def perc_down(self, i):
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while (i * 2) <= self.current_size:
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mc = self.min_child(i)
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if self.heap_list[i] > self.heap_list[mc]:
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tmp = self.heap_list[i]
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self.heap_list[i] = self.heap_list[mc]
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self.heap_list[mc] = tmp
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i = mc
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def min_child(self, i):
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if (i * 2 + 1) > self.current_size:
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return i* 2
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else:
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if self.heap_list[i * 2] < self.heap_list[i * 2 + 1]:
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return i * 2
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else:
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return i * 2 + 1
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def del_min(self):
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ret_val = self.heap_list[1]
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self.heap_list[1] = self.heap_list[self.current_size]
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self.current_size -= 1
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self.heap_list.pop()
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self.perc_down(1)
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return ret_val
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def build_heap(self, a_list):
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i = len(a_list) // 2
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self.current_size = len(a_list)
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self.heap_list = [0] + a_list[:]
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while (i > 0):
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self.perc_down(i)
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i -= 1
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heap = BinHeap()
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heap.build_heap([9, 6, 5, 2, 3])
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#heap.insert(5)
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#heap.insert(3)
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#heap.insert(9)
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#heap.perc_down()
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print("done")

‎BinaryTree_UsingListofLists.py

Lines changed: 66 additions & 0 deletions
Original file line numberDiff line numberDiff line change
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def binary_tree(n):
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return [n,[],[]]
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def insert_left(root,new_value):
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t = root.pop(1)
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if len(t) > 1:
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root.insert(1,[new_value,t,[]])
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else:
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root.insert(1,[new_value,[],[]])
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return root
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def insert_right(root,new_value):
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t = root.pop(2)
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if len(t) > 1:
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root.insert(2,[new_value,[],t])
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else:
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root.insert(2,[new_value,[],[]])
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return root
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def get_root_val(root):
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return root[0]
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def set_root_val(root, new_val):
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root[0] = new_val
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def get_left_child(root):
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return root[1]
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def get_right_child(root):
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return root[2]
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def build_tree():
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x = binary_tree('a')
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insert_left(x,'b')
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insert_right(x,'c')
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insert_right(get_left_child(x),'d')
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insert_left(get_right_child(x),'e')
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insert_right(get_right_child(x),'f')
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return x
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print(build_tree())
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"""
43+
x = binary_tree('a')
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insert_left(x,'b')
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insert_right(x,'c')
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print x
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insert_right(get_right_child(x), 'd')
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print x
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insert_left(get_right_child(get_right_child(x)), 'e')
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print x
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# another tree
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r = binary_tree(3)
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print(r)
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insert_left(r, 4)
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insert_left(r, 5)
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insert_right(r, 6)
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insert_right(r, 7)
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print(r)
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l = get_left_child(r)
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print(l)
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set_root_val(l, 9)
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print(r)
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insert_left(l, 11)
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print(r)
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print(get_right_child(get_right_child(r)))"""

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