题解 | #合法IP#
合法IP
https://www.nowcoder.com/practice/995b8a548827494699dc38c3e2a54ee9
ip_addr = input()
list = list(ip_addr.split("."))
flag = 0
for li in list:
if li:
if int(li) >=0 and int(li) <= 255 and str(int(li)) == li:
flag=flag+1
else:
break
print("YES" if flag == 4 else "NO")
