def ipv4_to_decimal(ipv4_address: str) -> int:
"""
Convert an IPv4 address to its decimal representation.
Args:
ip_address: A string representing an IPv4 address (e.g., "192.168.0.1").
Returns:
int: The decimal representation of the IP address.
>>> ipv4_to_decimal("192.168.0.1")
3232235521
>>> ipv4_to_decimal("10.0.0.255")
167772415
>>> ipv4_to_decimal("10.0.255")
Traceback (most recent call last):
...
ValueError: Invalid IPv4 address format
>>> ipv4_to_decimal("10.0.0.256")
Traceback (most recent call last):
...
ValueError: Invalid IPv4 octet 256
"""
octets = [int(octet) for octet in ipv4_address.split(".")]
if len(octets) != 4:
raise ValueError("Invalid IPv4 address format")
decimal_ipv4 = 0
for octet in octets:
if not 0 <= octet <= 255:
raise ValueError(f"Invalid IPv4 octet {octet}")
decimal_ipv4 = (decimal_ipv4 << 8) + int(octet)
return decimal_ipv4
def alt_ipv4_to_decimal(ipv4_address: str) -> int:
"""
>>> alt_ipv4_to_decimal("192.168.0.1")
3232235521
>>> alt_ipv4_to_decimal("10.0.0.255")
167772415
"""
return int("0x" + "".join(f"{int(i):02x}" for i in ipv4_address.split(".")), 16)
def decimal_to_ipv4(decimal_ipv4: int) -> str:
"""
Convert a decimal representation of an IP address to its IPv4 format.
Args:
decimal_ipv4: An integer representing the decimal IP address.
Returns:
The IPv4 representation of the decimal IP address.
>>> decimal_to_ipv4(3232235521)
'192.168.0.1'
>>> decimal_to_ipv4(167772415)
'10.0.0.255'
>>> decimal_to_ipv4(-1)
Traceback (most recent call last):
...
ValueError: Invalid decimal IPv4 address
"""
if not (0 <= decimal_ipv4 <= 4294967295):
raise ValueError("Invalid decimal IPv4 address")
ip_parts = []
for _ in range(4):
ip_parts.append(str(decimal_ipv4 & 255))
decimal_ipv4 >>= 8
return ".".join(reversed(ip_parts))
if __name__ == "__main__":
import doctest
doctest.testmod()