Phone Directory

Codewars Kata 45√

Description

https://www.codewars.com/kata/566584e3309db1b17d000027/solutions/python

-简述：本题给定通讯录里的一些信息，包括人名、电话号码、地址。要求查找到所需的电话号码对应的人名和地址，考虑不止一人或未找到的情况。
-思路：运用正则表达式，分类讨论。
-难点：1 通讯录里的格式有些不一样的，要考虑周全。

John keeps a backup of his old personal phone book as a text file. On each line of the file he can find the phone number (formated as +X-abc-def-ghij where X stands for one or two digits), the corresponding name between < and > and the address.

Unfortunately everything is mixed, things are not always in the same order, lines are cluttered with non-alpha-numeric characters.

Examples of John’s phone book lines:

”/+1-541-754-3010 156 Alphand_St. \n"

” 133, Green, Rd. NY-56423 ;+1-541-914-3010!\n"

“ +48-421-674-8974 Via Quirinal Roma\n"

Could you help John with a program that, given the lines of his phone book and a phone number returns a string for this number : “Phone => num, Name => name, Address => adress”

Examples:

s = “/+1-541-754-3010 156 Alphand_St. \n 133, Green, Rd. NY-56423 ;+1-541-914-3010!\n"

phone(s, “1-541-754-3010”) should return “Phone => 1-541-754-3010, Name => J Steeve, Address => 156 Alphand St.”

It can happen that, for a few phone numbers, there are many people for a phone number -say nb- , then

return : “Error => Too many people: nb”

or it can happen that the number nb is not in the phone book, in that case

return: “Error => Not found: nb”

You can see other examples in the test cases.

JavaScript random tests completed by @ matt c

Note Codewars stdout doesn’t print part of a string when between < and >

My solution

import re

def domain_name(url):
    mod_url = re.sub(r'[^A-Za-z0-9\+\-\<\>\.\']|/d+',' ',url)
    name1 = mod_url.split('<')[-1].split('>')[0]
    return 'Name => ' + name1

def domain_phone(url):
    mod_url = re.sub(r'[^A-Za-z0-9\+\-\<\>\.\']|/d+', ' ', url)
    del_name = mod_url.split('<')[0] + mod_url.split('>')[-1]
    phone1 = del_name.split('+')[-1].split(' ')[0]
    return phone1

def domain_address(url):
    mod_url = re.sub(r'[^A-Za-z0-9\+\-\<\>\.\']|/d+', ' ', url)
    del_name = mod_url.split('<')[0] + mod_url.split('>')[-1]
    mod_add = del_name.split('+')[0]+del_name.split('+')[-1].split(' ', 1)[-1]
    x = re.split(r'[^A-Za-z0-9\-\.\']+', mod_add.strip())
    add1 = ' '.join(x)
    return 'Address => '+add1

def phone(strng,num):
    split_strng = re.split(r'\n', strng.strip())
    count = 0
    for each_strng in split_strng:
        each_phone = domain_phone(each_strng)
        if each_phone == num:
            count += 1
            rst_strng = each_strng
    if count>1:
        return 'Error => Too many people: ' + num
    elif count == 0:
        return 'Error => Not found: '+ num
    else:
        phone = 'Phone => '+domain_phone(rst_strng)
        name = domain_name(rst_strng)
        addr = domain_address(rst_strng)
        rst = phone+', '+name+', '+addr
        return str(rst)

Given solution

from re import sub

def phone(dir, num):
    if dir.count("+" + num) == 0:
        return "Error => Not found: " + num
    
    if dir.count("+" + num) > 1:
        return "Error => Too many people: " + num
    
    for line in dir.splitlines():#按照换行符分割，每行为一项
        if "+" + num in line:
            name = sub(".*<(.*)>.*", "\g<1>", line)
            line = sub("<" + name + ">|\+" + num, "", line)
                #name和num用''代替，相当于删掉name和num
            address = " ".join(sub("[^a-zA-Z0-9\.-]", " ", line).split())
                #除数字、字母、点、-以外的全部替换为' '空格
                #split()不带参数时以空格进行分割，带参数时以该参数进行分割
            return "Phone => %s, Name => %s, Address => %s" % (num, name, address)

Improved solution:

import re

def phone(strng,num):
    if strng.count('+'+num)==0:
        return 'Error => Not found: ' + num
    elif strng.count('+'+num)>1:
        return 'Error => Too many people: ' + num
    for line in strng.splitlines():
        if '+' + num in line:
            name1 = re.sub('.*<(.*)>.*', '\g<1>', line)
            mod_url = re.sub('<' + name1 + '>|\+' + num, '', line)
            x = re.split(r'[^A-Za-z0-9\-\.\']+', mod_url.strip())
            add1 = ' '.join(x)
            return 'Phone => %s, Name => %s, Address => %s' %(num,name1,add1)

Points

1 split()当不带参数时以空格进行分割，当代参数时，以该参数进行分割。

2 \g<1>
In addition to character escapes and backreferences as described above, \g will use the substring matched by the group named name, as defined by the (?P...) syntax. \g uses the corresponding group number; \g<2> is therefore equivalent to \2, but isn’t ambiguous in a replacement such as \g<2>0. \20 would be interpreted as a reference to group 20, not a reference to group 2 followed by the literal character '0'. The backreference \g<0> substitutes in the entire substring matched by the RE. https://docs.python.org/3.2/library/re.html

3 splitlines() 按照换行符分割，每行为一项
splitlines()方法语法：
str.splitlines([keepends])
参数
keepends – 在输出结果里是否保留换行符(‘\r’, ‘\r\n’, \n’)，默认为 False，不包含换行符，如果为 True，则保留换行符。

4 符号’|’代表左右表达式任意匹配一个

5 str.count(string) 求字符串中某个部分string出现的次数
count()方法语法：
str.count(sub, start= 0,end=len(string))
参数
sub – 搜索的子字符串
start –字符串开始搜索的位置。默认为第一个字符,第一个字符索引值为0。
end –字符串中结束搜索的位置。字符中第一个字符的索引为0。默认为字符串的最后一个位置。

ps: 正则真好用。

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