Python 基礎教學

這份投影片適用的對象是已經具有基礎程式能力，至少熟悉一門程式語言的人，所有的程式都採用 Python 3

Transcript

1. #BTJD1ZUIPO
   NTUST Coding Club — Inndy
   

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2. 㛇劥Ꟛ涮橇㞯
   ˙⯝顥箁♳Ꟛ涮橇㞯IUUQTDJP
   ˙♳铭涸湱ꡠ须俲IUUQTKNQODDBEWQZ
   ˙*1ZUIPOIUUQTJQZUIPOPSH
   

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3. 簮䱖莅玑䒭⼦㝆
   a = input("a: ")
   if int(a) == 1:
   print("A is 1")
   else:
   print("A is not 1")
   3
   

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4. 簮䱖莅玑䒭⼦㝆
   • Ӟ㮆婘矎դ蔭Ӟ㮆纷ୗ玟璸
   • 磪ٛ蒈磪婘矎
   • 磪ٛ蒈಍磪婘矎牧犋胼㫂婘矎
   • ೲ Tab
   • Python 秂伛傶ࢥ㮆܎୵绚ጮ牧IDLE䨝䒻֦旉矦
   • if, for, while, with, class, def, try ...etc.
   4
   

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5. a = input("a: ")
   if int(a) == 1:
   print("A is 1")
   else:
   print("A is not 1")
   5
   

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6. a = input("a: ")
   if int(a) == 1:
   print("A is 1")
   else:
   print("A is not 1")
   6
   

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7. a = input("a: ")
   if int(a) == 1:
   print("A is 1")
   else:
   print("A is not 1")
   ग़訏ጱ婘矎牫
   7
   

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8. a = input("a: ")
   if int(a) == 1:
   print("A is 1")
   else:
   print("A is not 1")
   ग़訏ጱ婘矎牫
   8
   

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9. ⴅ䒭EFG
   碍䋊獢碍物
   Python獢ୗ物 def f(x, y):
   res = x * 3
   res += 5 * y ** 2
   return res
   f (x, y) = 3x + 5y2
   9
   

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10. ⴅ䒭EFG
    def 獢ୗݷ圸(㷢碍1, 㷢碍2, …):
    # 獢ୗ獉਻
    return Something
    10
    

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11. ⴅ䒭EFG
    • 蜍獈虻碘牧螀ᓒҁ牧蜍ڊ奾ຎ҂
    • 犖ݢ犥犋ࢧ㯽
    • ᯿蕦ጱ纷ୗ䌃౮獢ୗ牧ݢ犥᯿蕦ڥአ牧ො׎狕硬
    • 犋ٚ襑ᥝک蒂蕦蕣揳Ӥ
    11
    

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12. def add(x, y):
    result = x + y
    return result
    result = add(5, 6)
    print(result)
    12
    

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13. def add(x, y):
    result = x + y
    return result
    result = add(5, 6)
    print(result)
    ࢥ㮆܎୵绚ጮ
    13
    

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14. ⴅ䒭EFG箻绢
    1. 旉౮碍ਁ୵眲ҁint҂
    2. ፘ仂஑کଙ请ҁA - B҂
    3. ࢧ㯽奾ຎҁreturn҂
    14
    def YearToAge(birth):
    ....
    箻绢㻨♧ⴅ䒭鱒Ⰵⴀ欰䎃⟨銯⯋䎃⚛㔐⫄䎃룲
    塅ֺ蜍ڊ物
    ڊኞଙ犩ҁᥜزଙ҂物1995
    ֦犡ଙ 19 䵇ԧ
    

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15. JGⴼ倬哭⟝
    if 礿կ1:
    # 纷ୗ粙ྦྷ 1
    elif 礿կ2:
    # 纷ୗ粙ྦྷ 2
    # else-if ݢ犥盄ग़㮆
    # ౲ᘏ䷱磪
    elif 礿կ3:
    # 纷ୗ粙ྦྷ 3
    else:
    # ইຎ獮ᶎӣ殻礿կ᮷犋ᒧݳ
    15
    

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16. JGⴼ倬哭⟝
    a = input("Input a number:")
    a = int(a)
    if a > 5:
    print("a is bigger than 5")
    print("First branch")
    elif a < 3:
    print("a is smaller than 3")
    a = a + 5
    else:
    print("a is between 3 and 5")
    print("a = ", a)
    16
    

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17. JGⴼ倬哭⟝
    a = input("Input a number:")
    a = int(a)
    if a > 5:
    print("a is bigger than 5")
    print("First branch")
    elif a < 3:
    print("a is smaller than 3")
    a = a + 5
    else:
    print("a is between 3 and 5")
    print("a = ", a)
    17
    

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18. JG哭⟝ⴼ倬箻绢
    ˙ 锞鱒Ⰵⴀ欰䎃⟨銯⯋䎃⚛⚂ⴼ倬僽や䧭䎃
    ˙ ⢪欽ⶍⶍ涸:FBS5P"HFⴅ䒭
    18
    塅ֺ蜍ڊ物
    ڊኞଙ犩ҁᥜزଙ҂物1995
    ֦౮ଙԧ
    塅ֺ蜍ڊ物
    ڊኞଙ犩ҁᥜزଙ҂物1999
    ֦蝡㮆ੜ疵਎
    

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19. GPS鶬㕖
    19
    for i in iterable:
    print(i)
    

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20. JUFSBCMF
    ݢ犥ᤩ吚֢iteratorֵአጱ
    20
    

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21. ➊랃僽JUFSBUPS
    21
    

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22. 22
    22
    ➊랃僽JUFSBUPS
    

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23. 23
    23
    ➊랃僽JUFSBUPS
    

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24. 24
    24
    ➊랃僽JUFSBUPS
    

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25. 25
    25
    ➊랃僽JUFSBUPS
    

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26. ➊랃僽JUFSBUPS
    26
    26
    

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27. ➊랃僽JUFSBUPS
    27
    27
    

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28. Ջ讕ฎiterator牫
    28
    28
    JUFSBUPS
    

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29. Ջ讕ฎiterator牫
    • ℂ਻瑊獉瞟ڊྯӞ㮆زᔰጱૡٍ
    • ℂፋৼ獉ጱᒫӞ㮆ᇔߝ蚎ک磧盅Ӟ㮆ᇔߝ
    • 犋஠橕ஞፋৼ愊ᶎ裾Ջ讕䰬ৼ
    29
    

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30. for 蝅瑹
    30
    for i in [1, 3, 5]:
    print(i)
    1
    3
    5
    

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31. for 蝅瑹
    31
    for i in [1, 3, 5]:
    print(i)
    1
    3
    5
    list
    

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32. for 蝅瑹
    32
    for i in "ASD":
    print(i)
    A
    S
    D
    

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33. for 蝅瑹
    33
    for i in range(1, 4):
    print(i)
    1
    2
    3
    

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34. for 蝅瑹
    34
    for i in range(1, 10, 3):
    print(i)
    1
    4
    7
    

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35. for 蝅瑹
    35
    sum = 0
    for i in range(1, 11):
    sum += i
    print(sum)
    

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36. GPS鶬㕖
    
    data = ""
    for i in range(40, 60):
    data += chr(i)
    print(data)
    print(ord("A"))
    

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37. range獢ୗ
    37
    range(stop)
    # ۱珀 start ֕犋۱珀 stop
    range(start, stop)
    range(start, stop, step)
    # Example
    range(3) # [0, 1, 2]
    range(1, 4) # [1, 2, 3]
    range(8, 2, -2) # [8, 6, 4]
    range(3, 0, -1) # [3, 2, 1]
    

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38. GPS SBOHF竸ざ箻绢
    • 懯ᓒ 1 + 5 + 9 + 13 + 17 + … + 9997 ԏ者޾
    • 懯ᓒ 100! % 123456789012345 ҁ褩犔҂
    • 懯ᓒ 12 + 22 + 32 + 42 + … + 1002
    38
    sum = 0
    for i in range(1, 11):
    sum += i
    print(sum)
    

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39. ⳯讍鶋㺙岁
    
    mode = input("1 = ےੂ 2 = 薹ੂ物")
    data = input("蜍獈ᥝےੂጱ虻碘物")
    output = "" # 伛猋አ㬵硯奾ຎ
    for i in data: # 玲ڊ蜍獈ጱྯӞ㮆ਁ
    n = ord(i) # 旉矦౮ ASCII 嘨
    if mode == "1":
    n = n + 5 # ےੂ
    else:
    n = n - 5 # 薹ੂ
    c = chr(n) # ℂ ASCII 旉ࢧਁԀ
    output += c # ಩ےੂ / 薹ੂਠጱਁԀ蚏㬵
    print(output)
    

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40. 鶬㕖涸䱾ⵖ
    • break 泷ӤӾ䥁蝅瑹
    • continue 泷Ӥ᪡کӥӞ稞䁆ᤈ
    • else ইຎ蝅瑹䁆ᤈਠԧ䷱磪ᤩ break
    
    

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41. 鶬㕖涸䱾ⵖ
    
    for i in range(10):
    if i % 2 == 0:
    continue
    print(i)
    

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42. 㼦䪪_涸颶侸
    
    颶侸
    ꤑ✫莅荈䊹尝剤Ⱖ➮姻侮侸涸㔔侸
    

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43. 㼦䪪_涸颶侸
    ˙ 睨岁增叆僽やⰨ剤Ⱖ➮㔔侸
    ˙ O O佖葻睨岁涸眕㕠
    ˙ 4JFWFPG&SBUPTUIFOFT⿾麕⢵⨞涸睨岁
    ˙ 鼩剤Ⱖ➮刿㢵刿隶䢀刿醳꧹涸倰岁
    
    

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44. 㼦䪪_涸颶侸
    
    for i in range(2, 100 + 1):
    for j in range(2, i):
    if i % j == 0:
    break
    else: # ইຎ䷱磪ᤩbreak
    print(i, "is prime.")
    

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45. 8IJMF鶬㕖
    • 犖ฎӞ圵蝅瑹
    • ݝᥝ瞲ਧጱ礿կ౮缏疰Ӟፗ䁆ᤈ
    • while {condition}:

    do_some_thing("this")

    and_some_thing("that", 3, 4, 5)
    
    

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46. 8IJMF鶬㕖
    
    i = 10
    m = 1
    while i > 1:
    m *= i
    i -= 1
    print(m)
    

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47. # 娞聜物糔碍ਁ蝿瞁 http://j.mp/py-guess-num
    from random import randint
    r = randint(1, 10)
    print("I have a random number: ", r)
    secret = _______(1, 100) # 㫂碍
    _____ True: # 蝅瑹
    guess = input("Guess a number:")
    guess = ___(_____) # ਁԀ牫碍ਁ牫
    if _____ __ ______: # 糔䌘ԧ牫
    print("You got it!")
    _____ # 蝿瞁奾๳
    elif _____ _ ______: # ইຎ糔ॡय़ԧ
    print("Lower please.")
    else:
    print("Bigger and bigger.")
    

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48. -JTU
    ˙ 겳⡂"SSBZ
    ˙ 䖎㢵匌銯佞㖈♧饱꧌⚥盘椚
    ˙ 嫦⦐匌銯鿪剤♧⦐管贫*OEFY
    ˙ 䖰Ꟛ㨥鼹
    
    

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49. -JTU
    • empty_list = []
    • nums = [1,2,3,4,5,6] # nums[0] == 1
    • nums[0] = 9
    • nums.append(7)
    • nums += [8, 9, 10]
    • print(nums[2:5])
    • data = [1,[2,3,4],5]
    
    

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50. -JTU
    
    a = [1, 2, 3, 4, 5] # List
    for num in a:
    print(num)
    print("a[2] is", a[2])
    a.append(333)
    print(a)
    

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51. -JTU
    
    a = [4, 6, 3, 9, 1]
    a.sort()
    print(a)
    

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52. -JTU
    • min
    • max
    • sorted
    • reversed
    • sum
    
    

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53. -JTU
    
    䒊用♧⦐MJTU〭⨞QSJNFT
    ⚛⚂㖈酭꬗佞_涸颶侸
    搭䖕⽫ⴀ痧_⦐颶侸
    #FTNBSU锞♶銴QSJNFT >
    

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54. 0099(BNF
    
    http://j.mp/py-ooxx-game
    

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55. 㥶卓⡹銴-JTU剤_䙦랃⨞
    䖎矦㋲㉇欽GPS
    
    

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56. 56
    a = []
    for i in range(1, 11):
    a.append(i)
    欽GPS鶬㕖
    

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57. 
    a = [ i for i in range(1, 11) ]
    -JTU$PNQSFIFOTJPO
    

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58. 
    a = list(range(1, 11))
    85'
    

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59. 銴-JTU剤_䙦랃⨞
    䖎矦㋲㉇欽GPS
    
    

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60. 60
    a = []
    for i in range(1, 11):
    a.append(i ** 2)
    欽GPS鶬㕖
    

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61. 
    a = [i ** 2 for i in range(1, 11)]
    -JTU$PNQSFIFOTJPO
    

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62. -JTU$PNQSFIFOTJPO
    
    [ {expr} for i in {iter} ]
    [ {expr} for i in {iter} if {cond} ]
    

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63. -JTU$PNQSFIFOTJPO
    
    a = [ i * 2 for i in range(5) ]
    # [0, 2, 4, 6, 8]
    

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64. -JTU$PNQSFIFOTJPO
    
    b = [i for i in range(8) if i % 2 == 1]
    # [1, 3, 5, 7]
    

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65. -JTU$PNQSFIFOTJPO
    
    箻绢
    ⴪ⴀ 
    ⴪ⴀ 
    

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66. 
    print([
    n
    for n in range(2, 100)
    if not any(
    n % i == 0 for i in range(2, n)
    )
    ])
    -JTU$PNQSFIFOTJPO
    

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67. 
    print([
    n
    for n in range(2, 100)
    if not any(
    n % i == 0 for i in range(2, n)
    )
    ])
    -JTU$PNQSFIFOTJPO
    FYQSFTTJPO GPS DPOEJUJPO
    

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68. 
    print([
    n
    for n in range(2, 100)
    if not any(
    n % i == 0 for i in range(2, n)
    )
    ])
    -JTU$PNQSFIFOTJPO
    FYQSFTTJPO GPS DPOEJUJPO
    FYQSFTTJPO GPS
    

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69. TUS欽岁
    
    "ABCDEFG"[2:4]
    "Repeat Me" * 16
    "some" in "something is here"
    "this" not in "what about that"
    print("\n".join(["A", "B", "C"]))
    

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70. 竸ざ箻绢
    
    欽♧妄QSJOU⽫ⴀ⟃♴㕬䕎
    *
    **
    ***
    ****
    *****
    ******
    ******
    *****
    ****
    ***
    **
    *
    *
    ***
    *****
    *******
    

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71. 竸ざ箻绢
    
    欽♧妄QSJOU⽫ⴀ⟃♴㕬䕎
    3, 1 ___*
    2, 3 __***
    1, 5 _*****
    0, 7 *******
    

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72. 㶶⚮贖椚
    • s[:5] # 玲ڊ獮Բ㮆ਁ
    • s[-3:] # 玲ڊ磧盅ӣ㮆ਁ
    • s[0:4] # 玲ڊᒫ0㮆کᒫ3㮆ਁ
    • s[3:12:2] # 玲ڊᒫ3㮆کᒫ11㮆ਁ牧֕ฎྯ稞螂Ӟ
    㮆ҁ2-1҂
    4VCTUSJOH
    

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73. 㶶⚮贖椚
    • "ababa".count("a") # 3
    • "dcba".startswith("dc")
    • "abcd".endswith("d")
    • "AbcD".upper() # 旉य़䌃
    • "AbcD".lower() # 旉ੜ䌃
    

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74. 㶶⚮贖椚
    • "\n".join(['a', 'b', 'c'])
    • "ab cd ef".split(" ")
    • "fly in sky".index("in")
    • "123".zfill(5) # 酢ꨫ
    • ZJOTLZSFQMBDF JO PO
    
    

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75. 㶶⚮贖椚
    def is_mirror(s):
    return s == s[::-1]
    㔐俒ⴼ倬♧遤晝劥
    

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76. %JDU
    ˙ %JDUJPOBSZ
    ˙ ,FZ7BMVF
    ˙ *OEFY〳⟃僽⟤⡦匌銯涸-JTU
    • d = { "A": "A string", "B": 456.7 }
    
    

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77. %JDU
    • d[123] = 456
    • d['key'] = 'value'
    • d.update({'mixin': ‘this-dict'})
    • print(d.keys())
    • print(d.get('no-this-key', 123))
    • del d['a']
    
    

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78. %JDU
    for key, val in d.items():
    print("%s -> %s" % (key, val))
    
    

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79. %JDU
    e = { i: '(%04d)' % i for i in range(5) }
    print(e)
    
    

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80. %JDU
    e = { i: '(%04d)' % i for i in range(5) }
    print(e)
    
    

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81. 墂呪贖椚
    
    墂呪そ珖
    

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82. 墂呪贖椚
    
    墂そ
    墂そ墂呪涸そ㶶荈䊹《
    

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83. 墂呪贖椚
    
    ⶰ墂そ陏ⴽ墂呪涸겳㘗
    ⶰ墂そ
    

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84. 墂呪贖椚
    
    8JOEPXT涸ⶰ墂そ갸鏤♶곏爚
    

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85. 墂呪贖椚
    
    墂呪騟䖜穪㼩騟䖜㸤侮騟䖜
    

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86. 墂呪贖椚
    
    墂呪騟䖜湱㼩騟䖜
    

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87. 墂呪贖椚
    • fo = open("file name", "mode")
    • fo.write("data to write")
    • fo.readline()
    • fo.readlines()
    • fo.read(length)
    • fo.close()
    87
    

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88. 墂呪贖椚
    • r物捝玲
    • w物䌃獈ҁ薟荠碉㮆䲆礯҂
    • a物ᴫےҁ䌃獈ک䲆礯ੲᒒ҂
    • b物覍෈ਁ䲆礯秇ୗ
    • +物窾ݳ秇ୗҁݢ捝ݢ䌃҂
    
    䎙珏䌢鋅涸墂呪Ꟛ㉬垸䒭
    

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89. 墂呪贖椚
    • r+ ݢ捝ݢ䌃
    • ab ᴫےکӞ㮆 binary 䲆礯
    • wb ୌ缏౲竃绚Ӟ㮆 binary 䲆礯牧ݢ犥䌃獈
    
    䎙珏䌢鋅涸墂呪Ꟛ㉬垸䒭
    

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90. 90
    name = input("What is your name? ")
    file_obj = open("test.txt", "w")
    file_obj.write("Hi, " + name + "\n")
    file_obj.close()
    墂呪贖椚
    

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91. 91
    name = input("What is your name? ")
    file_obj = open("test.txt", "w")
    file_obj.write("Hi, " + name + "\n")
    file_obj.close()
    Ꟛ㉬墂呪 墂呪そ珖 Ꟛ㉬垸䒭
    ꡠꟗ墂呪 㻨Ⰵ墂呪 䳖遤
    墂呪贖椚
    

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92. 92
    fo = open("primes.txt", "r")
    s = 0
    for i in fo:
    s += int(i)
    print("Sum =", s)
    fo.close()
    墂呪贖椚
    

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93. 93
    fo = open("primes.txt", "r")
    s = 0
    for i in fo:
    s += int(i)
    print("Sum =", s)
    fo.close()
    墂呪贖椚
    

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94. 娞聜物dict 膏䲆礯
    94
    ˙ 䪾EJDU㶸鹎墂呪
    ˙ 䖰墂呪隡㔐EJDU
    

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95. 5FYU &ODPEJOHBOE#JOBSZ
    
    TUS CZUFT
    CZUFBSSBZ
    MJTUPGJOU
    >
    

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96. $PNNPO&SSPS
    )BOEMJOH
    try: parse_data()
    except Exception as e: print(e)
    

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97. 7BMVF&SSPS
    s = input("Give me a number: ")
    try:
    n = int(s)
    print(s, "^2 =", n * n)
    except ValueError:
    print(s, "is not a valid number")
    97
    

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98. 'JMF/PU'PVOE&SSPS
    try:
    fobj = open("readme.txt", "r")
    print(fobj.read())
    fobj.close()
    except FileNotFoundError:
    print("File 'readme.txt' not found")
    98
    

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99. 5ZQF&SSPS
    s = input('Give me a number: ')
    print("ready for an error?")
    print(s + 5)
    99
    

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100. *OEFY&SSPS
     months = ("Jan Feb Mar Apr May Jun Jul " +
     "Aug Sep Oct Nov Dec").split(" ")
     try:
     m = int(input("Which month? "))
     print("Month #" + str(m) + " is " +
     months[m - 1])
     except ValueError:
     print("Not a valid integer")
     100
     

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101. ,FZ&SSPS
     data = {
     "name": "Lightning",
     "type": "Pet",
     "age": 5,
     "weight": 18
     }
     while True:
     column = input("Which column? ")
     if not column: break
     print(data[column])
     101
     

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102. ;FSP%JWJTJPO&SSPS
     print("Input some numbers")
     s, n = 0, 0
     while True:
     m = input()
     if not m: break
     s += int(m)
     n += 1
     print("Avg = " + str(s / n))
     102
     

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103. *T"%JSFDUPSZ&SSPS
     fobj = open('this-is-directory', 'r')
     # 玱ྋ䨝㽆梊藮牧獵ӥጱ纷ୗ嘨፜ኼ
     103
     

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104. $47
     $PNNB4FQBSBUFE7BMVFT
     鸊贫ⴕꥬ须俲
     

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105. $47
     Name,Age,Score
     Quentin,23,79
     Marti,24,54
     Avelina,19,51
     Gayle,24,49
     Kimiko,18,64
     Chara,18,51
     April,19,40
     Alina,24,86
     105
     

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106. $478SJUFS3FBEFS
     import csv, sys
     try:
     filename = sys.argv[1]
     fobj = open(filename, 'w')
     writer = csv.writer(fobj)
     writer.writerow(['Name', 'Age'])
     writer.writerows([['lady gaga', 28],
     ['linroex', 19]])
     fobj.close()
     except IndexError:
     print("Usage: python3 " +
     sys.argv[0] + " output.csv")
     106
     

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107. $478SJUFS3FBEFS
     import csv, sys
     try:
     filename = sys.argv[1]
     fobj = open(filename, 'r')
     reader = csv.reader(fobj)
     skip_first_line = True
     for row in reader:
     if skip_first_line:
     skip_first_line = False
     continue
     print(row)
     fobj.close()
     except IndexError:
     print("Usage: python3 " +
     sys.argv[0] + " output.csv")
     except FileNotFoundError:
     print("File not found -> " + filename)
     107
     

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108. $MBTTBOE0CKFDU
     ˙ $MBTTˋ겳ⴽ
     ˙ 鏤鎙㕬䒊眡话㕬
     ˙ .FUIPEˋ倰岁㿂倴暟⟝涸ⴅ䒭
     ˙ 0CKFDUˋ暟⟝
     ˙ 㻜넓欴ㅷ覈ⴀ⢵涸䒊眡暟
     ˙ "UUSJCVUFˋ㿂䚍꣡⸈倴暟⟝涸须俲
     108
     

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109. $MBTTBOE0CKFDU
     109
     def FirstClass:
     def __init__(self, name):
     print('Hi, %s' % name)
     first_object = FirstClass('Inndy')
     print(first_object)
     

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110. $MBTTBOE0CKFDU
     110
     def FirstClass:
     def __init__(self, name):
     print('Hi, %s' % name)
     def leaving(self):
     print('Bye, %s' % self.name)
     obj = FirstClass('Inndy')
     obj.leaving()
     print(obj)
     

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111. $MBTTBOE0CKFDU
     class Animal:
     def __init__(self, name, sound = None):
     self.name = name
     self.sound = sound
     def say_hi(self):
     if self.sound == None:
     print("Hi, I'm " + self.name)
     else:
     print(self.name, ":", self.sound * 7)
     cat = Animal("Cat", "meow~") # init
     cat.say_hi()
     cat.sound = None
     cat.say_hi()
     112
     

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