huffmantree.py has many error, so it's useless #482

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1. jackson-dahl42 commented on May 13, 2024

   

   jackson-dahl42

   on May 13, 2024

   Last edited by jackson-dahl42

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   Hello vmailhot, I tried fixing the code in the file.

   from heapq import heapify as hpf
   from heapq import heappop as hpp
   from heapq import heappush as hppu

   class Node:
   def init(self, ch, freq, left=None, right=None):
   self.ch, self.freq = ch, freq
   self.left, self.right = left, right
   def lt(self, other):
   return self.freq < other.freq

   def getHuffmanTree(txt):
   if len(txt) == 0:
   return
   freq = {ch: txt.count(ch) for ch in set(txt)}
   pq = [Node(k, v) for k, v in freq.items()]
   hpf(pq)
   while len(pq) > 1:
   left, right = hpp(pq), hpp(pq)
   newFreq = left.freq + right.freq
   hppu(pq, Node(None, newFreq, left, right))
   root = pq[0]
   return root

   def printTree(node, level=0, prefix=''):
   if node is not None:
   print(' ' * level + prefix + str(node.freq))
   if node.left is not None or node.right is not None:
   printTree(node.left, level + 1)
   printTree(node.right, level + 1)

   root = getHuffmanTree("hello world")
   printTree(root)