AoC 2021 16 I iterator version

AoC_2021_16_1_iter.py

def versions(data):
    while data:
        yield int(data[:3], 2)
        ptype = int(data[3:6], 2)
        data = data[6:]
        if ptype == 4:
            while data[0] == "1":
                data = data[5:]
            data = data[5:]
        else:
            ltype = data[0]
            if ltype == "0":
                data = data[16:]
            else:
                data = data[12:]


hexstr = open("input_16.txt").read().strip()
packet = "".join(f"{int(ch, 16):04b}" for ch in hexstr)
result = sum(v for v in versions(packet))
print(result)