牛客網初級專案筆記（一）

使用pip進行安裝requests和beautifulsoup4庫，程式碼為：

pip install requests
pip install beautifulsoup

之後進行糗事百科的爬取：

#coding=utf-8
 
import requests
from bs4 import BeautifulSoup
 
content=requests.get('http://www.qiushibaike.com').content
soup=BeautifulSoup(content,'html.parser')
 
for div in soup.find_all('div',{'class':'content'}):
    print div.text.strip()

python基本語法：

#coding=utf-8
 
import requests
import random
import re
from bs4 import BeautifulSoup
 
def qiushibaike():
    content=requests.get('http://www.qiushibaike.com').content
    soup=BeautifulSoup(content,'html.parser')
 
    for div in soup.find_all('div',{'class':'content'}):
        print div.text.strip()
 
 
def demo_string():
    stra='hello world world'
    #首字母大寫，其餘小寫
    print stra.capitalize()
    #替換所有的world為nowcoder
    print stra.replace('world','nowcoder')
    strb='   \n\r hello nowcoder \r\n'
    #去掉左邊的空格和回車
    print 1,strb.lstrip()
    #去掉右邊的空格和回車
    print 2,strb.rstrip()
    strc='hello w'
    print 3,strc.startswith('hel')
    print 4,strc.endswith('x')
    print 5,stra+strb+strc
    print 6,len(strc)
    print 7,'-'.join(['a','b','c'])
    print 8,strc.split(' ')
    print 9,strc.find('ello')
 
def demo_operation():
    print 1,1+2,5/2,5*2,5-2
    print 2,True, not True
    print 3,1<2,5>2
    print 4,2<<3
    print 5,5|3,5&3,5^3
    x=2
    y=3.3
    print x,y,type(x),type(y)
 
 
def demo_buildinfunction():
    print 1,max(2,1),min(5,3)
    print 2,len('xxx'),len([1,2,3])
    print 3,abs(-2)
    print 4,range(1,10,3)
    print 5,dir(list)
    x=2
    print 6,eval('x+3*x')
    print 7,chr(65),ord('a')
    print 8,divmod(11,2)
 
def demo_controlflow():
    score=65
    if score>99:
        print 1,'A'
    elif score>60:
        print 2,'B'
    else:
        print 3,'C'
    while score<100:
        print score
        score+=10
    score=65
 
    #continue,break,pass
    for i in range(0,10,2):
        if i==0:
            pass #do special什麼也不做
            # print 3,i
        if i<5:
            continue
        print 3,i
        if i==6:
            break
 
 
def demo_list():
    lista=[1,2,3] #vector ArrayList
    print 1,lista
    listb=['a',1,'c',1.1]
    print 2,listb
    lista.extend(listb)
    print 3,lista
    print 4,len(lista)
    print 5,'a' in listb
    lista=lista+listb
    print 6,lista
    listb.insert(0,'www')
    print 7,listb
    listb.pop(1)
    print 8,listb
    listb.reverse()
    print 9,listb
    print 10,listb[0],listb[1]
    listb.sort()
    print 11,listb[0],listb[1]
    listb.sort(reverse=True)
    print 12,listb
    print 13,listb*2
    print 14,[0]*14
    tuplea=(1,2,3)
    listaa=[1,2,3]
    listaa.append(4)
    print 15,listaa
 
def add(a,b):
    return a+b
def sub(a,b):
    return a-b
 
#類似於HashMap
def demo_dict():
    dicta={4:16,1:1,2:4,3:9}
    print 1,dicta
    print 2,dicta.keys(),dicta.values()
    print 3,dicta.has_key(1),dicta.has_key('3')
    for key,value in dicta.items():
        print 'key-value:',key,value
    #類似於函式指標
    dictb={'+':add,'-':sub}
    print 4,dictb['+'](1,2)
    print 5,dictb.get('-')(15,3)
    dictb['*']='x'
    print dictb
    dicta.pop(4)
    print 6,dicta
 
#集合
def demo_set():
    lista=[1,2,3]
    seta=set(lista)
    setb=set((2,3,4))
    print 1,seta
    # seta.add(4)
    # print 2,seta
    print 3,seta.intersection(setb),seta&setb
    print 4,seta|setb,seta.union(setb)
    print 5,seta-setb
    seta.add(1)
    print 6,seta
 
class User:
    type='USER'
    def __init__(self,name,uid):
        self.name=name
        self.uid=uid
    def __repr__(self):
        return ' im '+self.name+' '+str(self.uid)
 
class Admin(User):
    type = 'ADMIN'
    def __init__(self,name,uid,group):
        User.__init__(self,name,uid)
        self.group=group
    def __repr__(self):
        return ' im '+self.name+' '+str(self.uid)+' '+self.group
 
class Guest(User):
    def __init__(self,name,uid):
        User.__init__(self, name, uid)
    def __repr__(self):
        return ' im guest '+self.name+' '+str(self.uid)
def create_user(type):
    if type=='USER':
        return User('u1',1)
    elif type=='ADMIN':
        return Admin('a1',101,'g1')
    else:
        return Guest('g1',100)
 
#異常
def demo_exception():
    try:
        print 2/1
        raise Exception('Raise Error','Nowcoder')
    except Exception as e:
        print 'error',e
    finally:
        print 'clean up'
 
 
#隨機數
def demo_random():
    #1-100
    random.seed(1)
    #x=prex*10007%xxxx
    #prex=x 冪等性
    print 1,int(random.random()*100)
    print 2,random.randint(0,200)
    print 3,random.choice(range(0,100,10))
    print 4,random.sample(range(0,100),4)
 
    a=[1,2,3,4,5]
    random.shuffle(a)
    print 5,a
 
 
def demo_re():
    str='abc123def12gh15'
    '''
    \d數字
    \D非數字
    \s 空格,\r\t
    \S 
    \w [0-9][a-z][A-Z]
    \W
    + 至少匹配1次
    * 至少匹配0次
    '''
    p1=re.compile('[\d]+')
    p2=re.compile('\d')
    print 1,p1.findall(str)
    print 2,p2.findall(str)
 
    str='a@163.com;b@gmail.com;c@qq.com;e@163.com;z@qq.com'
    p3=re.compile('[\w]+@[163|qq]+\.com')
    print p3.findall(str)
 
    str='<html><h>title</h><body>xxx</body></html>'
    p4=re.compile('<h>[^<]+</h>')
    print 4,p4.findall(str)
 
    p4 = re.compile('<h>([^<]+)+</h><body>([^<]+)</body>')
    print 5, p4.findall(str)
 
    str='xx2016-06-11yy'
    p5=re.compile('\d{4}-\d{2}-\d{2}')
    print p5.findall(str)
 
if __name__=='__main__':
    demo_re()
    # demo_random()
    # demo_exception()
    # user1=User('u1',1)
    # print user1
    # admin1=Admin('a1',101,'g1')
    # print admin1
    #
    # print create_user('ANDJ')
    # print 'hello nowcoder'
    #comment
    # demo_string()
    # demo_operation()
    # demo_buildinfunction()
    # demo_controlflow()
    # demo_list()
    # demo_dict()
    # demo_set()