- 写一个正则表达式判断一个字符串是否是ip地址
规则：一个ip地址由4个数字组成，每个数字之间用.连接。每个数字的大小是0-255
255.189.10.37 正确
256.189.89.9 错误
def is_ip(ip: str):
ip_re = r'(([1-9](\.|\d\.))|(1\d\d\.|2([0-4]\d\.|5[0-5]\.))){3}(([1-9](|\d))|(1\d\d|2([0-4]\d|5[0-5])))'
if fullmatch(ip_re, ip):
return True
return False
print(is_ip('255.189.89.9'))
# re_num = r'(([1-9]|[1-9]\d|1\d\d|2[0-4]\d|25[0-5])\.){3}([1-9]|[1-9]\d|1\d\d|2[0-4]\d|25[0-5])'
- 计算一个字符串中所有的数字的和
例如：字符串是：‘hello90abc 78sjh12.5’ 结果是90+78+12.5 = 180.5
def sum_num(str1: str):
re_str = r'\d+[.]\d+|\d+'
result = findall(re_str, str1)
sum1 = 0
for num in result:
sum1 += float(num)
return sum1
# re_str = r'[+-]?([1-9]\d*|0)(\.\d+)?'
print(sum_num('hello90abc 78sjh12.5'))
- 验证输入的内容只能是汉字
def is_chinese(str1: str):
re_str = r'[\u4e00-\u9fa5]+'
if fullmatch(re_str, str1):
return True
return False
- 电话号码的验证
def is_phone_num(str1: str):
re_str = r'^1[3-9]\d{9}$'
if fullmatch(re_str, str1):
return True
return False
- 验证输入用户名和QQ号是否有效并给出对应的提示信息
要求：
用户名必须由字母、数字或下划线构成且长度在6~20个字符之间
QQ号是5~12的数字且首位不能为0
def username_qq_check(username: str, qq_num: str):
username_re = r'[a-zA-Z\d_]{6,20}'
qq_num_re = r'[1-9]\d{4,11}'
result1 = fullmatch(username_re, username)
result2 = fullmatch(qq_num_re, qq_num)
if result1 and result2:
return 'username and qq_num check ok!'
else:
if result1:
return "username check ok,qq_num check fail\ntips:qq_num must be all numbers, and first num can't be 0! "
elif result2:
return "qq_num check ok,username check fail\ntips:username must composed of 6 to 20 num or alpha or _"
else:
return "check fail\n" \
"qq_num must be all numbers, and first num can't be 0!\n" \
"username must composed of 6 to 20 num or alpha or _"
- 拆分长字符串：将一首诗的中的每一句话分别取出来
poem = '窗前明月光，疑是地上霜。举头望明月，低头思故乡。'
def split_poem(poem: str):
poem_re = r'[\u4e00-\u9fa5]+'
lines = findall(poem_re, poem)
for line in lines:
print(line)
split_poem(poem)
二、不定项选择题
- 能够完全匹配字符串“(010)-62661617”和字符串“01062661617”的正则表达式包括（D）
A. “(?\d{3})?-?\d{8}”
B. “[0-9()-]+”
C. “[0-9(-)]\d”
D. “[(]?\d[)-]\d*”
2.能够完全匹配字符串“c:\rapidminer\lib\plugs”的正则表达式包括（B）
A. “c:\rapidminer\lib\plugs”
B. “c:\rapidminer\lib\plugs”
C. “(?i)C:\RapidMiner\Lib\Plugs” ?i:将后面的内容的大写变成小写
D. “(?s)C:\RapidMiner\Lib\Plugs” ?s：单行匹配
3.能够完全匹配字符串“back”和“back-end”的正则表达式包括（A ）
A. “\w{4}-\w{3}|\w{4}”
B. “\w{4}|\w{4}-\w{3}”
C. “\S+-\S+|\S+”
D. “\w\b-\b\w|\w*”
4.能够完全匹配字符串“go go”和“kitty kitty”，但不能完全匹配“go kitty”的正则表达式包括（D）
A. “\b(\w+)\b\s+\1\b”
B. “\w{2,5}\s*\1”
C. “(\S+) \s+\1”
D. “(\S{2,5})\s{1,}\1”
5.能够在字符串中匹配“aab”，而不能匹配“aaab”和“aaaab”的正则表达式包括（B）
A. “a*?b”
B. “a{,2}b”
C. “aa??b”
D. “aaa??b”