题解 | #牛客网的IP地址#

# 获取输入的字符串
str1 = input()

# 判断是否合法
str_list = str1.split(".")
if len(str_list)!=4:
    print("illegal")
else:
    for i in str_list:
        if i=='':
            print("illegal")
            break
        elif int(i)>255 or int(i)<0:
            print("illegal")
            break
    else:
        print("legal")