【Python爬虫類】-【第1週】02-宿題練習:

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愚かな方法学python電子書籍の中で次の練習問題27-34
練習問題27:論理関係を覚える.

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27

① ;

② + 4 + , ;

③ : ( ), ( ), ( )。

--NOT--

not False = True

not True = False

--OR--

True or False = True

True or True = True

False or True = True

False of False = False

-- AND --

True and False = False

True and True = True

False and True = False

False and False = False

--NOT OR ----

not(True or False) = False

not(True or Ture) = False

not(False or True) = False

not(False or False) = True

---NOT AND----

not(True and False) = True

not(True and True) = False

not(False and True) = True

not(False and False) = True

---!=---

1 != 0 True

1 != 1 False

0 != 1 True

0 != 0 Fase

-----== ----

1 == 0 False

1 == 1 True

0 == 1 False

0 == 0 True

28: ;

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28

!=

print ("1.", True and True) # True
print ("2.", False and True) # False
print ("3.", 1 == 1 and 2 == 1) #False
print ("4.", "test" == "test") #True
print ("5.", 1 == 1 or 2 != 1) #True
print ("6.", True and 1 == 1) # True
print ("7.", False and 0 != 0) #False
print ("8.", True or 1 == 1) #True
print ("9.", "test" == "testing") #False
print ("10.", 1 != 0 and 2 == 1) #False
print ("11.", "test" != "testing") #True
print ("12.", "test" == 1) #False
print ("13.", not (True and False)) #True
print ("14.", not (1 == 1 and 0 != 1)) #False
print ("15.", not (10 == 1 or 1000 == 1000)) #False
print ("16.", not (1 != 10 or 3 == 4)) #False
print ("17.", not ("testing" == "testing" and "Zed" == "Cool Guy")) #True
print ("18.", 1 == 1 and not ("testing" == 1 or 1== 0)) #True
print ("19.", "chunkey" == "bacon" and not (3 == 4 or 3 == 3)) #False
print ("20.", 3 == 3 and not ("testing" == "testing" or "Python" == "Fun")) #False

1. : 〈〉 or != , < or <=, > or >=,

2. :

+ plus

- minus

/ slash

* asterisk

% percent

< less - than

> greater - than

<= less - than - equal

>= greater - than - equal

== equal equal

!= not equal

29: (if)

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29: (if)

people = 20
cats = 30
dogs = 15

if people < cats:
print ("Too many cats! The world is doomed!")

if people > cats:
print ("Not many cats! The world is saved!")

if people < dogs:
print ("The world is drooled on!")

if people > dogs:
print ("The world is dry!")

dogs += 5
if people >= dogs:
print ("People are greater than or equal to dogs.")
if people <= dogs:
print ("People are less than or equal to dogs.")

if people == dogs:
print ("People are dogs.")

1.if

2.python , 4 , tab , , 4

3. , , ;

4. ,true ,false if if

5. , if , 。


.

30:Else if;

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30:Else and if

people = 70
cars = 10
buses = 200

if cars > people:
print ("We should take the cars.")
elif cars < people or buses < cars:
print ("We should not take the cars.")
else:
print ("We cat't decide.")

if buses > cars:
print ("That's too many buses.")
elif buses < cars:
print ("Maybe we could take the buses.")
else:
print ("We still can't decide.")

if people > buses:
print ("Alright,let's just take the buses.")
else:
print ("Fine,let's stay home then.")

1.elif if ,else

31: ;

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31 :

python3.6 raw_input(), input()

print ("You enter a dark room with two doors. Do you
go through door #1 or door #2?")

door = input("> ")

if door == "1":
print ("There's a giant bear here eating a cheese cake.
What do you do?")
print ("1. Take the cake.")
print ("2. Scream at the bear.")

bear = input("> ")

if bear == "1":
    print ("The bear eats your face off. Good job!")
elif bear == "2":
    print ("The bear eats your legs off.Good job!")
else:
    print ("Well ,doing %s is probably better. Bear runs away." % bear)

elif door == "2":
print ("You stare into the endless abyss at Cthulhu's retina.")
print ("1. Blueberries.")
print ("2. Yellow jacket clothespins.")
print ("3. Understanding revolvers yelling melodies.")

insanity = input("> ")

if insanity == "1" or insanity == "2":
    print ("Your body survives powered by a mind of jello.Good job!")
else:
    print ("The insanity rots your eyes into a pool of muck.Good job!")

else:
print ("You stumble around and fall on a knife and die. Good job!")

32: ;

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32 :

the_count = [1, 2, 3, 4, 5]
fruits = ['apples', 'oranges', 'pears', 'apricots' ]
change = [1, 'pennies', 2, 'dimes', 3, 'quarters']

this first kind of for-loop goes through a list

for number in the_count:
print ("This is count %d" % number)

same as above

for fruit in fruits:
print ("A fruit of type: %s" % fruit)

also we can go through mixed lists too

notice we have to use %r since we don't know what's in it

for i in change:
print ("I got %r" % i)

we can also build lists, first start with an empty one

elements = []

then use the range function to do 0 to 5 counts

for i in range(0, 6):
print ("Addming %d to the list." % i)
#append is a function that lists understand
elements.append(i)

now we can print them out too

for i in elements:
print ("Element was: %d" % i)

2. 22 , , elements = list(range(0,6))

3.append extend ,insert ,index ,sort ,count ,reverse ,pop ,remove()

33:While ;

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33 while

while loop False , :( ,colon)

i = 0
numbers = []

while i < 6:
print ("At the top i is %d" % i)
numbers.append(i)
i = i + 1
print ("Numbers now:", numbers)
print ("At the bottom i is %d" % i)

print ("The numbers: ")

for num in numbers:
print (num)

34: ;

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34

animals = ['bear', 'python', 'peacock', 'kangaroo', 'whale', 'platypus']

print ("The 1st animal is at 0 and is a", animals[1-1], ".")
print ("The animal at 0 is the 1st animal and is a", animals[1-1], ".")

print ("The 2st animal is at 1 and is a", animals[2-1], ".")
print ("The animal at 1 is the 2st animal and is a", animals[2-1], ".")

print ("The 3st animal is at 2 and is a", animals[3-1], ".")
print ("The animal at 2 is the 3st animal and is a", animals[3-1], ".")

print ("The 4st animal is at 3 and is a", animals[4-1], ".")
print ("The animal at 3 is the 4st animal and is a", animals[4-1], ".")

print ("The 5st animal is at 4 and is a", animals[5-1], ".")
print ("The animal at 4 is the 5st animal and is a", animals[5-1], ".")

print ("The 6st animal is at 5 and is a", animals[6-1], ".")
print ("The animal at 5 is the 6st animal and is a", animals[6-1], ".")

print ("*" * 50)
print ("select for-loop")
j = 0
for i in animals:
j = j + 1
print ("The %d st animal is at %d and is a %s." % (j, j-1 ,animals[j-1]))
print("The animal at %d is the %d st animal and is a %s." % (j-1, j, animals[j-1]))