1. 已知字串 a = "aasmr3idd4bgs7dlsf9eaf",要求如下
1.1 請將a字串的大寫改為小寫，小寫改為大寫。
a = "aasmr3idd4bgs7dlsf9eaf"
print(a.swapcase())
'''a = "aasmr3idd4bgs7dlsf9eaf"
b =
for n in a :
if "a"<= n <= "z":
elif"a" <= n <= "z" :
else:
print("".join(b))'''
a = "aasmr3idd4bgs7dlsf9eaf"
print("".join([s for s in a if s.isdigit()]))
'''a = "aasmr3idd4bgs7dlsf9eaf"
b =
for n in a :
if "0"<= n <= "9":
print("".join(b))'''
a = "aasmr3idd4bgs7dlsf9eaf"
a=a.lower()
print(dict([(x,a.count(x)) for x in set(a) if not x.isdigit()]))
'''a = "aasmr3idd4bgs7dlsf9eaf"
b = {}
for n in a :
m=n.lower()
if "a"<= m<= "z":
b[m]=b.get(m,0)+1
print(b)'''
a = "aasmr3idd4bgs7dlsf9eaf"
b=list(a)
c=list(set(b)) #set轉換為集合，去重，無序
c.sort(key=b.index)
print ("".join(c))
'''a = "aasmr3idd4bgs7dlsf9eaf"
b =
for n in a :
if "a"<= n.lower() <= "z":
if n not in b:
else:
print("".join(b))'''
a = "aasmr3idd4bgs7dlsf9eaf"
print (a[::-1]) #步進
a = "aasmr3idd4bgs7dlsf9eafc"
b=for x in a:
c=ord(x)
if x.isupper():
c+=31.5 #chr("a")=97
if c>=65: #chr("a")=65,去掉數字 或者 if not x.isdigit()
c=b.sort()
for x in b:
if x%1==0.5:
x-=31.5
d=chr(int(x)) #將65.0轉換為65，再轉換為"a"
print("".join(c))
a = "aasmr3idd4bgs7dlsf9eafc"
b=[x for x in a if not x.isdigit()]
c=sorted(b,key=str.lower,reverse=true)
print ("".join(c)[::-1])
a = "aasmr3idd4bgs7dlsf9eafc"
b="boy"
c=set(a)
c.update(list(b))
print (len(set(a))==len(c))
a = "aasmr3idd4bgs7dlsf9eafc"
b=["boy","girl","bird","dirty"]
c=set(a)
for i in b:
c.update(list(i))
print (len(set(a))==len(c))
a = "aasmr3idd4bgs7dlsf9eaf"
b=[(x,a.count(x)) for x in set(a) if not x.isdigit()]
b.sort(key=lambda k:k[1],reverse=true)
print(b[0][0])
import os
m=os.popen("python -m this").read()
m=m.replace("\n","")
l=m.split(" ")
print ([(x,l.count(x)) for x in ["be","is","than"]])
size=102324123499123
print ("%s kb"%(size>>10))
print ("%s mb"%(size>>20))
a = [1,2,3,6,8,9,10,14,17]
print (str(a)[1:-1].replace(", ",""))
'''a = [1,2,3,6,8,9]
print (str(a)[1:-1:3])'''#如果位數相同可使用步進的方法
a="3211423243"
b=str.maketrans("123","abc","12") #前兩個引數位數一致，一一對應進行替換。最後乙個引數是刪除其中的字元
#a.translate("12") #第二個引數代表逐字元刪除
print (a.translate(b))
#輸出結果：c4c4c
ainfo =
5.1 迭代字典，輸出結果：
('a', 'haha')
('c', 'hehe')
('b', 'python')
('f', 'xiaoming')
ainfo =
a=["a","c","b","f"]
for x in a:
print ((x,ainfo[x]))
ainfo =
print ([x for x,y in ainfo.items() if y=="haha"])
a = 123
b = 345
c = 444
def text():
"返回這3個數字中最大的乙個"
a = 123
b = 345
c = 444
return max(a,b,c)
print (text())
def text2(a,b,c):
"返回這3個數字中最大的乙個"
return max(a,b,c)
print (text2(123,345,444))
提示一下用到函式的：**和*，猩猩是字典，星是元組
2.1 呼叫函式：ainfo(x=88,y=22,z=44) 你定義ainfo函式體裡面的內容並且返回結果：
[22, 44, 88]
def ainfo(**tmp):
return sorted(list(tmp.values()))
print (ainfo(x=88,y=22,z=44))
('xaay','yaay','zaay')
def ainfo(**tmp):
return tuple([x+"aay" for x in tmp.keys()])
print (ainfo(x=88,y=22,z=44))
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