Aditya
39 lines
929 B
Python
39 lines
929 B
Python
def build_tree(freq):
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nodes = [[freq[ch], ch] for ch in freq] # each node = [weight, data]
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while len(nodes) > 1:
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nodes = sorted(nodes, key=lambda x: x[0])
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left = nodes.pop(0)
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right = nodes.pop(0)
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new = [left[0] + right[0], [left, right]] # merge
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nodes.append(new)
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return nodes[0]
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def assign(node, code="", table={}):
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if isinstance(node[1], str): # leaf
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table[node[1]] = code
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else:
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left, right = node[1]
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assign(left, code+"0", table)
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assign(right, code+"1", table)
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return table
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def huffman(text):
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# freq count
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freq = {}
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for c in text:
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freq[c] = freq.get(c, 0) + 1
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# build + assign
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root = build_tree(freq)
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codes = assign(root)
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# print
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for ch in sorted(codes):
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print(ch, ":", codes[ch])
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txt = "abbbbbbcccddddddddee"
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huffman(txt)
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