vize2.py

class Node:
    freq = None
    left = None
    right = None
    letter = None

    def __init__(self, freq, left=None, right=None, letter=None):
        self.freq = freq
        self.left = left
        self.right = right
        self.letter = letter


def build_tree(freqs):
    l = [Node(x, None, None, freqs[x]) for x in freqs.keys()]
    i = 0

    while len(l) > i + 1:
        (a, b) = l[i:i + 2]

        s = a.freq + b.freq

        idx = next((index for index, node in enumerate(l) if node.freq > s), len(l))
        l.insert(idx, Node(s, a, b))

        i += 2

    return l[-1]


def decode(tree, code):
    decoded = []
    node = tree

    for i in code:
        node = node.left if i == str(0) else node.right

        if not node.left and not node.right:
            decoded.append(str(node.letter))
            node = tree
            continue

    return ''.join(decoded)


def main():
    tree = build_tree({
        20: 'R',
        25: 'B',
        30: 'L',
        33: 'G',
        43: 'I',
        70: 'A',
        79: 'E'
    })

    decoded = decode(tree, '1111110000001110000101110')

    print(decoded)


if __name__ == "__main__":
    main()