题解 | #判断两个IP是否属于同一子网#

while True:
    try:
        mask=list(map(int,input().split('.')))
        ip1=list(map(int,input().split('.')))
        ip2=list(map(int,input().split('.')))
        flag=1
        for i in range(len(mask)):
            if mask[i] not in range(256) or ip1[i] not in range(256) or ip2[i] not in range(256):
                flag=0
                break
            elif i<len(mask)-1 and mask[i]<mask[i+1]:
                flag=0
                break
            else:
                continue
        a=[]
        b=[]
        for i in range(len(mask)):
            a.append(mask[i]&ip1[i])#python中对两个数值进行&运算，是把他们转换成2进制后再&运算
            b.append(mask[i]&ip2[i])
        if flag:
            if a==b:
                print('0')
            else:
                print('2')
        else:
            print('1')
    except:
        break