题解 | #判断两个IP是否属于同一子网#

def ip2int(ip):
    ret = 0
    ip_li = ip.split('.')
    for i in range(0, 4):
        v = int(ip_li[i])
        if not (0 <= v < 256):
            return -1
        ret += v * pow(256, 3 - i)
    return ret

def CheckSubNet(ip0, ip1, ip2):
    print(0 if (ip0 & ip1 == ip0 & ip2) else 2)

while True:
    try:
        ip0 = input()
    except EOFError:
        break
    try:
        ip1 = input()
    except EOFError:
        break
    try:
        ip2 = input()
    except EOFError:
        break
    ip0 = ip2int(ip0)
    ip1 = ip2int(ip1)
    ip2 = ip2int(ip2)
    if not(ip0 >= 0 and ip1 >= 0 and ip2 >= 0 and bin(ip0).find('01') < 0 and bin(ip0).__len__() == 34):
        print(1)
        continue
    CheckSubNet(ip0, ip1, ip2)