Павел
99 lines
2.7 KiB
Python
99 lines
2.7 KiB
Python
from copy import deepcopy
|
|
from ipaddress import IPv4Address
|
|
from typing import List, Tuple
|
|
|
|
|
|
def get_data(input_file):
|
|
with open(input_file, "r") as file:
|
|
data = file.read().splitlines()
|
|
return data
|
|
|
|
|
|
def cidr4_to_binary(cidr4: str) -> str:
|
|
ip_str, vlsm = cidr4.strip().split("/")
|
|
vlsm = int(vlsm)
|
|
ipv4 = IPv4Address(ip_str)
|
|
binary_ip = bin(int(ipv4))[2:]
|
|
binary_ip = binary_ip.zfill(32)
|
|
binary = binary_ip[:vlsm]
|
|
return binary
|
|
|
|
|
|
def binary_to_cidr4(binary: str) -> str:
|
|
vlsm = len(binary)
|
|
binary_ip = binary + "0" * (32 - vlsm)
|
|
int_ip = int(binary_ip, 2)
|
|
ip = IPv4Address(int_ip)
|
|
return f"{ip}/{vlsm}"
|
|
|
|
|
|
def reduce_binary(binary: str) -> str:
|
|
if len(binary) == 0:
|
|
return ""
|
|
new_binary = binary[:-1]
|
|
if "1" not in new_binary:
|
|
return ""
|
|
return new_binary
|
|
|
|
|
|
def rough_merge_binaries(binaries: List[str], req_len: int) -> List[str]:
|
|
ips = set(deepcopy(binaries))
|
|
non_reducible_ips = set()
|
|
reduction_limit_reached = False
|
|
while (
|
|
len(ips) > 0
|
|
and len(ips) + len(non_reducible_ips) > req_len
|
|
and not reduction_limit_reached
|
|
):
|
|
max_vlsm = len(max(ips, key=lambda x: len(x)))
|
|
reduced_ips = set()
|
|
merged_ips = set()
|
|
for ip in ips:
|
|
if len(ip) == max_vlsm:
|
|
reduced_ip = reduce_binary(ip)
|
|
if len(reduced_ip) > 0:
|
|
reduced_ips.add(reduced_ip)
|
|
else:
|
|
non_reducible_ips.add(ip)
|
|
else:
|
|
merged_ips.add(ip)
|
|
merged_ips.update(reduced_ips)
|
|
if len(merged_ips) + len(non_reducible_ips) > req_len:
|
|
ips = merged_ips
|
|
else:
|
|
reduction_limit_reached = True
|
|
|
|
ips.update(non_reducible_ips)
|
|
return sorted(ips)
|
|
|
|
|
|
def main():
|
|
file = "cidr4.txt"
|
|
required_len = 20
|
|
|
|
data = get_data(file)
|
|
bin_ips = list(map(cidr4_to_binary, data))
|
|
rough_merged_bin_ips = rough_merge_binaries(bin_ips, required_len)
|
|
print(f"{len(rough_merged_bin_ips)=}")
|
|
for ip in rough_merged_bin_ips:
|
|
print(ip)
|
|
|
|
|
|
if __name__ == "__main__":
|
|
assert cidr4_to_binary("4.78.139.0/24") == "000001000100111010001011"
|
|
assert cidr4_to_binary("128.0.0.0/1") == "1"
|
|
assert cidr4_to_binary("0.0.0.0/0") == ""
|
|
|
|
assert binary_to_cidr4("000001000100111010001011") == "4.78.139.0/24"
|
|
assert binary_to_cidr4("1") == "128.0.0.0/1"
|
|
assert binary_to_cidr4("") == "0.0.0.0/0"
|
|
|
|
assert reduce_binary("000001000100111010001011") == "00000100010011101000101"
|
|
assert reduce_binary("1") == ""
|
|
assert reduce_binary("0") == ""
|
|
assert reduce_binary("") == ""
|
|
assert reduce_binary("0001") == ""
|
|
assert reduce_binary("0000") == ""
|
|
|
|
main()
|