# 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")