python使用正则筛选信用卡

本文实例为大家分享了python使用正则筛选信用卡的具体代码，供大家参考，具体内容如下

本文来源于两个简单的题目：

1.判断一对单词是否是" Anagrams "
2.判断信用卡是否合理

判断 Anagramsstrong>

anagrams 的百度翻译：由颠倒字母顺序而构成的字（短语）

而题目给出例子：

[ DOG , ODG ]
[ DOG , DOG ]
[ DOG , GOD ]
[ DOG , GDO ]

均为 anagrams 。

那思路就简单了，直接拆分字母，排序，比较就 ok 。

判断信用卡

题目给出的要求如下：

The criteria are:
• It must start with a 4,5 or 6
• It must be exactly 16 digits
• It must be numbers only
• It can have a digits in groups of 4, separated by one hyphen “-“
• It should not contain any other characters.
• It must NOT have any 4 repeated digits.

样例输出如下：

378282246310005 Invalid
30569309025904 Invalid
6011111111111117 Invalid
5123-2332-3232-3213 valid

py文件

两个题目合并在一个 py 文件中。
而入参数分别是两个文件的名字，一个是 anagram.txt ，另一个是 credit_cards.txt ，他们分别长这样：

最后的程序长这样：

#! /usr/bin/python3
import re
###############################
##You need to implet the following methods:
##
##Question 1
##anagram_validator()
##
##Question 2
##credit_card_validator()

################################

###################################################
# Question 1: Check for anagrams:#
###################################################

def get_list(src_str):
sub_list=[]
word_tmp=''
for word in src_str:
if word != ',':
word_tmp = word_tmp+word
else:
sub_list.append(word_tmp)
word_tmp = ''
return sub_list

def read_anagram(file_name):
'''
Input: a file name
Return: a nested list of two words list
Example : [[word1,word2],[word3,word4]...etc]
'''
with open(file_name,encoding = 'utf-8') as f:
return_list =[]
file_conment = f.read()

file_conment_new = re.sub(r'\n',',',file_conment)
file_conment_new = file_conment_new+','
subs_list = get_list(file_conment_new)
i=0
while i < (len(subs_list)-1):
return_list.append([subs_list[i],subs_list[i+1]])
i=i+2
return return_list

def anagram_validator(anagram):
'''
Input is the output from "read_anagram()".
Return: list of "anagrams" or "Not anagrams" values for each two words
example input (dog,gdo),(try,elm) then output would be ["anagrams","Not anagrams"] with sequence of the input
'''
result_list=[]
for i in range(len(anagram)):
word_font = ''.join((lambda x:(x.sort(),x)[1])(list(anagram[i][0])))
word_back = ''.join((lambda x:(x.sort(),x)[1])(list(anagram[i][1])))
if word_font == word_back:
result_list.append('Anagrams')
else:
result_list.append('Not anagrams')

return result_list

############################################
# Question 2: Validate credit cards #
############################################
def read_credit_cards(file_name):
'''
Input: a file name
Return tuple of numbers
'''
with open(file_name,encoding='utf-8') as f:
card_conment = f.read()

card_conment = re.sub(r'\[','',card_conment)
card_conment = re.sub(r'\]','',card_conment)
card_conment = card_conment+','
card_list = get_list(card_conment)
return tuple(card_list)

def credit_card_validator(numbers):
'''
Input: tuple of numbers
Return:dictionary of credit card numbers where key is the number and value if valid or invalid
'''
validator_list=[]
credit_dict={}
for i in range(len(numbers)):
validator_list.append(numbers[i])

for i in range(len(numbers)):
ch_num = 0
repeat_flag = 0
for ch in validator_list[i]:
if ord("A")<=ord(ch)<=ord("Z"):
ch_num+=1
break

tmp_list = []
tmp_list = (re.sub(r"[^\d]", "", validator_list[i]))
for index in range(len(tmp_list)-4):
if(tmp_list[index] == tmp_list[index+1] and
tmp_list[index] == tmp_list[index+2] and
tmp_list[index] == tmp_list[index+3] ):
repeat_flag = 1
break;

if(validator_list[i][0] != '4' and
validator_list[i][0] != '5' and
validator_list[i][0] != '6' ):
credit_dict[validator_list[i]]='Invalid'
elif( len(re.sub(r"\D", "", validator_list[i])) != 16 ):
credit_dict[validator_list[i]]='Invalid'
elif(ch_num > 0):
credit_dict[validator_list[i]]='Invalid'
elif(
(re.search(r"-",validator_list[i])) and
 ( validator_list[i][4] != '-' or
 validator_list[i][9] != '-'or
 validator_list[i][14] != '-'
 )
):
credit_dict[validator_list[i]]='Invalid'
elif(re.search(r"[^-\d]",validator_list[i])):
credit_dict[validator_list[i]]='Invalid'
elif(repeat_flag == 1 ):
credit_dict[validator_list[i]]='Invalid'
else :
credit_dict[validator_list[i]]='Valid'
space_str = ''

return credit_dict

def print_credit_card_summary(dict_o):
'''
Input: dict
Return:
printing summary of validation result - space between credit card and status is 40 width
example:
378282246310005 Invalid
30569309025904 Invalid
'''
space_str = ''
for key in dict_o:
new_str = key + dict_o[key]
if(dict_o[key] == "Valid"):
new_str_tmp = new_str[:-5]
space_lenth = 46-len(new_str)
for x in range(space_lenth):
space_str +=' '
print(new_str_tmp + space_str + 'Valid')
space_str=''
else :
new_str_tmp = new_str[:-7]
space_lenth = 48-len(new_str)
for x in range(space_lenth):
space_str +=' '
print(new_str_tmp + space_str + 'Invalid')
space_str=''

####### THE CODE BELOW IS FOR TESTING###################
############### DO NOT CHANGE #########################

import sys

if __name__ == '__main__':
# Take care of the console inputs
if len(sys.argv) <= 1:
sys.argv = ['', "anagram.txt", "credit_cards.txt"]
stars = '*' * 40
print(stars)
print("Testing Question 1 --- Anagrams?")
print(stars)

# testing reading_anagrams
try:
anagram = read_anagram(sys.argv[1])
if not anagram:
print("read_anagram() returns None.")
else:
print("anagram: ", anagram)
print()
except Exception as e:
print("Error (readnumbers()): ", e)

# testing anagram_validator
Anagrams = 0
NAnagrams = 0
try:
if not anagram: # Question 1 has not been implemented
print("anagram_validator() skipped....")
else:
result = anagram_validator(anagram)
if result == None:
print("anagram_validator() returns None.")
else:
for i in result:
 if i == "Anagrams":
 Anagrams += 1
 elif i == "Not anagrams":
 NAnagrams += 1
print("Number of valid Anagrams is {} and Not anagrams is {}.".format(Anagrams, NAnagrams))

except Exception as e:
print("Error (anagram_validator()):", e)

# testing Question 2

print("\n\n" + stars)
print("Testing Question 2 --- Credit Card Validator")
print(stars)

# Testing reading_credit_cards
try:
tup = read_credit_cards(sys.argv[2])
if not tup:
print("read_credit_cards() returns None.")
else:
print("The tuple of credit_cards: {}".format(tup))
except Exception as e:
print("Error (read_credit_cards()):", e)

# Testing credit_card_validator
vcc = 0
ivcc = 0
try:
if not tup: # Readin_Question 2 has not been implemented
print("credit_card_validator() skipped...")
else:
cc_dict = credit_card_validator(tup)
tmp_cc_dict = cc_dict
if not cc_dict:
print("credit_card_validator() returns None.")
else:
for items in cc_dict.keys():
 if cc_dict[items] == "Valid":
 vcc += 1
 elif cc_dict[items] == "Invalid":
 ivcc += 1
print("Number of valid credit cards is {} and invalid {}.".format(vcc, ivcc))
except Exception as e:
print("Error (credit_card_validator()):", e)

# testing Question 2
print("\n\n" + stars)
print("Testing Question 2b --- Print Credit Card Summary")
print(stars)
# Testing print_credit_card_summary
try:
if not tmp_cc_dict: # Dict credit card output has not been implemented
print("print_credit_card_summary() skipped...")
else:
import io # do not delete this line
from contextlib import redirect_stdout # do not delete this line

f = io.StringIO()
with redirect_stdout(f):
print_credit_card_summary(tmp_cc_dict)
out = f.getvalue()
if not out:
print("print_credit_card_summary() returns None.")
else:
count44 = 0
count46 = 0
for line in out.splitlines():
 if len(line) - len(line.split()) == 44:
 count44 += 1
 elif len(line) - len(line.split()) == 46:
 count46 += 1
if count44 == vcc and count46 == ivcc:
 print("Your format looks good")
else:
 print("You might have some issues in your summary format")

except Exception as e:
print("Error (print_credit_card_summary()):", e)

来源：https://blog.csdn.net/qq_30650153/article/details/84110948