python

这里看不到页码，只能标节号,我所写出的都是可执行的,或者有错误的地方
这里修改回>>>号的展示模式
2.4

number = int('35', 8)
print(number)

import math
result = math.cos(2*(5+1)+3)/2
print(result)

2.5.1

x=1
y=2
k=x+y
print(k)

x,y=4,8
print(x,y)

a=b=c=5
print(a,b,c)
b =b+6
print(a,b,c)

i=2
i*=3+1 #i=i*(3+1)
print(i)

2.5.2这里

if后面多加一个空格

2.5.3

for i in [1,2,3,4]:print(i)

2.5.4

print(sum([1/i if i%4==1 else-1/i for i in list(range(1,50)) if i %2==1]))

2.7

a=5
b=17
print("　","{:>08s}".format(bin(a)[2 :]))
print("& ","{:>08s}".format(bin(b)[2 :]))
print("-----------")
print("　","{:>08s}".format(bin(a&b)[2 :]))

第三章
3.1.2

prompt='hello'
print(prompt[0])

prompt='hello'
print(prompt[4])

a=[2,3,5,7,11,13]
print(a[1 : 3])

a=[2,3,5,7,11,13]
b=a[:]
b[0]=1
print(a)

3.1.3

a=[2,3,5,7,11,13]
b=[4,6,8,9,10,12]
print(a+b)

a=[2,3,5,7,11,13]
print(3 in a)

a=[2,3,5,7,11,13]
[2,3] in a

b=[[2,3],5,6,11,13]
[2,3] in b

s='hello'
print('e' in s)
print('he' in s)

3.1.4

len([2,3,5,7])

len('hello world')

min([2,3,5,7,11,13])

min('好好学习天天向上')

min(['apple','orange','melon'])

3.2.1
这个复制不了，我只能截图了

3.2.2









3.2.3



3.3.1

3.3.2



3.3.3







3.3.4

把结果就是四个字删了

3.3.5



3.4

4.2.1

count=10
while count>0 :print(count)count-=1
print("发射!")

4.4.4

a=[80,58,73,90,31,92,39,24,14,79,46,61,31,61,93,62,11,52,34,17]
for right in range(len(a),0,-1):maxidx=0for i in range(1,right):if a[i]>a[maxidx]:maxidx=ia[maxidx],a[right-1]=a[right-1],a[maxidx]
print(a)

a=[80,58,73,90,31,92,39,24,14,79,46,61,31,61,93,62,11,52,34,17]
right=len(a)
for i in range(0,right-1):if a[i]>a[i+1]:a[i],a[i+1]=a[i+1],a[i]
print(a)

a=[80,58,73,90,31,92,39,24,14,79,46,61,31,61,93,62,11,52,34,17]
for right in range(len(a),0,-1):for i in range(0,right-1):if a[i]>a[i+1]:a[i],a[i+1]=a[i+1],a[i]print(a)

5.1.3

s={2,3,5,7,11}
print(5 in s)
print(4 not in s)

s1={2,3,5,7}
s2={1,2,3,4,5,6,7}
print(s1.issubset(s2))

s1={2,3,5,7}
s2={1,2,3,4,5,6,7}
print(s2.issuperset(s2))

s1={2,3,5,7}
s2={3,2,7,5}
print(s1==s2)

mailto=['cc','bbbb','afa','sss','bbbb','cc','shafa']
addr_to=list(set(mailto))
addr_to.sort(key=mailto.index) #key 参数代表排序规则
print(addr_to)

5.2.2

name={'2050921018':'詹延峰','2050921036':'李小鹏'}
name["2050921039"]="裴凡法"
print(name)
print(len(name))

name={'2050921018':'詹延峰','2050921036':'李小鹏','2050921039':'裴凡法'}
print('2050921018' in name)
print('2050151003' in name)

name1={'2050921018':'詹延峰','2050921036':'李小鹏','2050921039':'裴凡法'}
name2={'2050921018':'詹延峰','2050921036':'李大鹏','2050921039':'裴凡法'}
print(name1==name2)

name1={'2050921018':'詹延峰','2050921036':'李小鹏','2050151003':'裴凡法'}
name2={"2050151003":"韩平医",'2050921036':'李大鹏'}
print({∗∗name1,∗∗name2})

5.2.3

name={'2050921018':'詹延峰','2050921036':'李小鹏','2050921039':'裴凡法'}
lst=list(name.values())
print(lst)
print(name.pop('2050921039'))
print(name.get('2050921039'))

favorite_languages={'詹延峰':'python','李小鹏':'c','裴凡法':'ruby','韩平医':'python'}
for name,language in favorite_languages.items():print(name.title( ) + "'s favorite language is " +language.title() + ".")

days={1:"Mon",2:"Tue",3:"Wed",4:"Thu",5:"Fri",6:"Sat",7:"Sun"}
num=int(input())
print(days[num])

poly1={98: 2,5:-4,2: 3,0: 1}   #2x98-4x5+3x2+1
poly2={90: 7,5: 3,2:-3,1: 5}   #7x90+3x5-3x2+5x
poly3={}                       #两个多项式的和字典
deg=set(poly1) |set(poly2)     #和多项式可能的指数集合
for i in deg:                  #遍历指数coeff=poly1.get(i,0) +poly2.get(i,0)if coeff!=0:poly3[i]=coeff
print(poly3)

books={"name":["C#从入门到精通","ASP.NET 高级编程","Python 核心编程","JavaScript 大全","Django 简明教程","深入理解Python 语言"],"price":[45.7,34.6,56.9,47,35,89],"store":["京东","京东","淘宝","淘宝","当当","当当"]}
print(min(books["price"]))

第六章
6.1

def fibs(n):result=[0,1]for i in range(n-2):result.append(result[-2] +result[-1])return result
print(fibs(5))

g=lambda x,y,z:x+y+z　　#把lambda定义的匿名函数赋给函数
print(g(1,4,5))　　     #请注意g是函数,不是普通变量,它要像函数一样使用

6.2.1

from math import sqrt
def dis(x1,y1,x2,y2):　　#求平面上两点距离print("x1={},y1={},x2={},y2={}".format(x1,y1,x2,y2))return sqrt((x1-x2)∗∗2+(y1-y2)∗∗2)
print(dis(1,3,4,5))

from math import sqrt
def dis(x1,y1,x2,y2):　　#求平面上两点距离print("x1={},y1={},x2={},y2={}".format(x1,y1,x2,y2))return sqrt((x1-x2)∗∗2+(y1-y2)∗∗2)
print(dis(x1=1,y2=5,y1=3,x2=4))

from math import sqrt
def dis(x1,y1,x2,y2):　　#求平面上两点距离print("x1={},y1={},x2={},y2={}".format(x1,y1,x2,y2))return sqrt((x1-x2)∗∗2+(y1-y2)∗∗2)
print(dis(1,3,y2=5,x2=4))

from math import sqrt
def dis(x1,y1,x2,y2): #求平面上两点距离print("x1={},y1={},x2={},y2={}".format(x1,y1,x2,y2))return sqrt((x1-x2)∗∗2+(y1-y2)∗∗2)
print(dis(1,y1=3,4,5))

6.2.3

from math import sqrt
def dis(x1,y1,x2,y2=5):        #求平面上两点距离print("x1={},y1={},x2={},y2={}".format(x1,y1,x2,y2))return sqrt((x1-x2)∗∗2+(y1-y2)∗∗2)
print(dis(1,3,4))

from math import sqrt
def dis(x1,y1,x2,y2=5): #求平面上两点距离print("x1={},y1={},x2={},y2={}".format(x1,y1,x2,y2))return sqrt((x1-x2)∗∗2+(y1-y2)∗∗2)
print(dis(1,3,4,10))

def init(arg,result=[]):result.append(arg)print(result)init('a')
init('b')

def f(a,l=[]):l.append(a)return l
l1=f(10)
l2=f(123,[1,2,3])
l3=f("b")
print(l1)
print(l2)
print(l3)

6.2.4

def countnum(a,∗b): #计算参数个数print(b)print(len(b) +1)countnum(3,7,9)
countnum(5,8,1,6,89)

def countnum(a,∗∗d): #计算参数个数print(d)print(len(d)+1)
countnum(3,x1=9,x2=1,x3=6,x4=89)

6.3

lst=[2,3,5,8,3,6,8]
seen=set()
lst1=[i for i in lst if i not in seen and not seen.add(i)]
print(lst1)

def func1(par):
print(par)
def func2():print(1000)
def func3(par):print(2000)
def f(x):return {'a': func1,'b': func2,}.get(x,func3)f("a")(100)
f("c")(100)

6.4

def scope():var1=1print("函数内部打印结果")print(var1,var2)
var1=10
var2=20
scope()
print("函数外部打印结果")
print(var1,var2)

def scope():global var1var1=1print("函数内部打印结果")print(var1,var2)var1=10
var2=20
scope()
print("函数外部打印结果")print(var1,var2)

6.5

def fib(n):      #n是正整数
if n==0 or n==1:return 1
else:return fib(n-1)+ fib(n-2)
print(fib(4))

pre={0: 1,1: 1}
def fib(n):if n in pre: #可以用in 检查字典中是否有n 这个关键字return pre[n]else:newvalue=fib(n-1)+fib(n-2)pre[n]=newvalue #增加字典的条目return newvalue
print(fib(100))

def perm(choice,selected=[]):if len(choice)==0: #递归结束条件print("".join(selected),end=" ")else:for i in range(len(choice)):#对循环的每个字母,去掉后,求更短单词的排列perm ( choice [: i]+choice [ i+1:],selected.copy ( )+[ choice[i]])
s="abc"
perm(list(s))

def perm(choice,selected=[]):lst=[]if len(choice)==0: #递归结束条件lst.append(choice)#print(lst)return lstelse:for i in range(len(choice)):#对循环的每个字母,去掉后,求更短单词的排列shortperm=perm(choice[: i]+choice[i+1:],selected.copy( )+
[choice[i]])#对每一种排列,加上去掉的字母for k in shortperm:lst.append([choice[i]]+k)#print(lst)return lst
s="abc"
for element in perm(list(s),selected=[]):print("".join(element),end=" ")

6.7.1

def fac(n):
f=1
for i in range(1,n+1):f=f∗i
return f
print(__name__)
if __name__=="__main__":print(fac(5))