[Python] 6/49 Big Lottery 大樂透 程式, 過了今晚!

. [Python] 6/49 大樂透 程式, 過了今晚!.

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import random

lotterys = random.sample(range(1,50), 7)

specialNum = lotterys.pop()

print("大樂透 中獎號碼: ", end="")

for lottery in sorted(lotterys):

    print(lottery, end=" ")

print("\n特別號: ", specialNum)

print("過了今晚!")

執行結果範例:

PS D:\DevTool\ZCode> & C:/Python312/python.exe d:/DevTool/ZCode/_Code/_Python/BigLotterys.py

大樂透 中獎號碼: 13 19 22 34 40 43 

特別號:  32

過了今晚!

[Python] 字典 dict { } 的 key, value 鍵、值 互換

.[Python] 字典 dict { } 的 key, item 鍵、值 互換

 

--- --- --- --- --- --- --- --- ---

(1) 字典鍵值互換, 方法一 for 循環:

mydict = {'a': 1, 'b': 2, 'c': 3}

mydict_new = {}

for key, value in mydict.items():

    mydict_new[value] = key

print(mydict)

print(mydict_new)

---

>>> mydict = {'a': 1, 'b': 2, 'c': 3}

>>> mydict_new = {}

>>> for key, value in mydict.items():

...      mydict_new[value] = key

...

>>> print(mydict)

{'a': 1, 'b': 2, 'c': 3}

>>> print(mydict_new)

{1: 'a', 2: 'b', 3: 'c'}

>>>

--- --- --- --- --- --- --- --- ---

(2) 字典鍵值互換, 方法二 列表生成器 generator:

mydict = {'a': 1, 'b': 2, 'c': 3}

mydict_new = dict([value, key] for key, value in mydict.items())

print(mydict)

print(mydict_new)

---

>>> mydict = {'a': 1, 'b': 2, 'c': 3}

>>> mydict_new = dict([value, key] for key, value in mydict.items())

>>> print(mydict)

{'a': 1, 'b': 2, 'c': 3}

>>> print(mydict_new)

{1: 'a', 2: 'b', 3: 'c'}

--- --- --- --- --- --- --- --- ---

(3) 字典鍵值互換, 方法三 zip:

mydict = {'a': 1, 'b': 2, 'c': 3}

mydict_new = dict(zip(mydict.values(), mydict.keys()))

print(mydict)

print(mydict_new)

---

>>> mydict = {'a': 1, 'b': 2, 'c': 3}

>>> mydict_new = dict(zip(mydict.values(), mydict.keys()))

>>> print(mydict)

{'a': 1, 'b': 2, 'c': 3}

>>> print(mydict_new)

{1: 'a', 2: 'b', 3: 'c'}

[Python] 傳回 ASCII 的 chr() 函數 vs 傳回字元的 Unicode 碼值 ord() 函數

.[Python] 傳回 ASCII 的 chr() 函數 vs 傳回字元的 Unicode 碼值 ord() 函數

(1) 傳回 ASCII 的 chr() 函數:

>>> x1 = 65

>>> x2 = 66

>>> print(chr(x1))  // 或是 print(chr(65))

A

>>> print(chr(x2))  // 或是 print(chr(66))

B

>>>

---

>>> y1 = 97

>>> y2 = 98

>>> print(chr(y1))  // 或是 print(chr(97))

a

>>> print(chr(y2))  // 或是 print(chr(98))

b

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(2) 傳回字元的 Unicode 碼值 ord() 函數:

>>> ch11 = 'A'

>>> ch12 = 'B'

>>> print(ord(ch11))  // 或是 print(ord( 'A'))

65

>>> print(ord(ch12))  // 或是 print(ord( 'B'))

66

>>>

---

>>> ch21 = 'a'

>>> ch22 = 'b'

>>> print(ord(ch21))  // 或是 print(ord( 'a'))

97

>>> print(ord(ch22))  // 或是 print(ord( 'b'))

98

[Python] name_list.reverse() and name_list[::-1]

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(1) 方法1: name_list.reverse()

(2) 方法2: 使用 slice 切片 name_list[::-1]

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# Example 1:

python3

>>>

>>> cars = ['Honda', 'BMW', 'Toyota', 'Ford']

>>> cars

['Honda', 'BMW', 'Toyota', 'Ford']

>>> cars[::-1]

['BMW', 'Ford', 'Toyota', 'BMW', 'Honda']

>>> cars.reverse()

>>> cars

['Ford', 'Toyota', 'BMW', 'Honda']

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# Example 2:

>>> nums1 = [5, 3, 9, 2]

>>> nums1

[5, 3, 9, 2]

>>> nums2 = nums1[::-1]

>>> nums2

[2, 9, 3, 5]

>>> nums1.reverse()

>>> nums1

[2, 9, 3, 5]

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[Python] Remove elements from a list

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[Python] Remove elements from a list

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(1) Using the del keyword

(2) Using the list.remove(x) method

(3) Using the list.pop([x]) method

... ... ...

(1) Using the del keyword:

# Sample Code 1

list1 = [0, 1, 2, 3, 4, 5, 6]

del list1[0]

print(list1)

# [1, 2, 3, 4, 5, 6]

del list1[-1]

print(list1)

# [1, 2, 3, 4, 5]

del list1[:2]

print(list1)

# [3, 4, 5]

(2) Using the list.remove(x) method:

# Sample Code 2

list1 = [0, 1, 2, 3, 4, 5, 6]

list1.remove(2)

print(list1)

# [0, 1, 3, 4, 5, 6]

(3) Using the list.pop([x]) method:

# Sample Code 3

list1 = [0, 1, 2, 3, 4, 5, 6]

list1.pop()

print(list1)

# [0, 1, 2, 3, 4, 5]

list_removed = list1.pop(4)

print(list1)

# [0, 1, 2, 3, 5]

// End

[Python] Concatenate Lists / Merge Lists in Python

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[Python] Concatenate Lists / Merge Lists in Python

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(1) Concatenating Lists with "+" Operator

(2) Utilizing the Extend() Method

(3) Applying the Itertools.chain() Function

(4) Native Method for List Concatenation (list.append())

(5) List Comprehension to concatenate lists

... ... ...

[Python][Regular Expressions][正規表示式] Python’s Regex Symbols

... ... ...

[Regular Expressions][正規表示式] Python’s Regex Symbols

... ... ...

[Python] Python’s basic data types

.  Python’s basic data types .

[Python] Python String format 字串格式化 : (1) 舊式字串格式化 %-formatting (2) 新式字串格式化 str.format() (3) 字串插值 f-string (Formatted String Literal) (4) Template Strings

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Python 在處理字串時, 由於版本的演變, 有太多種方法, 所以很容易搞混. 筆記整理一下.

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(1) 舊式字串格式化 %-formatting:

string interpolation

初代 format string, 這是類似 C語言 printf 語法, 使用 % 格式, 

例如: %s (字串), %d (十進位整數), %f (浮點數), 將 tuple 中的一組變量依照指定字串格式輸出.

# Example 1.1:

text = 'World'

print('Hello %s' % text)

# Hello world

# Example 1.2:

name = "John"

age = 23

print('%s is %d years old.' % (name, age))

# John is 23 years old.

# Example 1.3:

print('%x' % 11)  # 轉成十六進位

# b

(2) 新式字串格式化 str.format()

Python 2.6 (發布於 2008 年), 開始有新式字串格式化 str.format(), 透過{} 和 format 來代替 % 運算符號.

# Example 2.1:

text = 'World'

print('Hello {0}'.format(text))

# Hello world

print('Hello {}'.format(text))

# Hello world

# Example 2.2:

name = "John"

age = 23

print('{0} is {1} years old.'.format(name, age))

# John is 23 years old.

print('{} is {} years old.'.format(name, age))

# John is 23 years old.

# Example 2.3:

print('{:x}'.format(11))  # 轉成十六進位

# b

# Example 2.4:

print('{:.2f}'.format(3.1416))  # 保留小數點後兩位

# 3.14

# Example 2.5:

print('{:+.2f}'.format(3.1416))  # 帶符號保留小數點後兩位

# +3.14

細節可以參考 Ref3: Python format 格式化函数

https://www.runoob.com/python/att-string-format.html

(3) 字串插值 f-string (Formatted String Literal)

Python 3.6 (發布於 2016 年) 新增 f-string, 解決變量不易閱讀以及變量超長的問題.

# Example 3.1:

text = 'World'

print(f'Hello {text}')

# Hello world

# Example 3.2:

name = "John"

age = 23

print(f'{name} is {age} years old.')

# John is 23 years old.

# Example 3.3:

print(f'{11:x}')  # 轉成十六進位

# b

# Example 3.4:

print(f'{3.1416:.2f}')  # 保留小數點後兩位

# 3.14

a = 3.1416

print(f'{a:.2f}')  # 保留小數點後兩位

# 3.14

# Example 3.5:

print(f'{3.1416:+.2f}')  # 帶符號保留小數點後兩位

# +3.14

細節可以參考 Ref4: 制霸 Python f-string 各種格式使用方法

https://myapollo.com.tw/blog/python-f-string-formating-syntax/

(4) Template Strings:

# Example 4.1:

from string import Template

name = 'Bob'

t = Template('Hey, $name!')

t.substitute(name=name)

# 'Hey, Bob!'

--- --- ---

同場加映 : Python String 字串 join() 語法

# Example 5.1:

chars = ['P', 'y', 't', 'h', 'o', 'n']

text = "".join(chars)

print(text)  # 顯示：Python

# Example 5.2:

chars = ['P', 'y', 't', 'h', 'o', 'n']

text = "##".join(chars)

print(text)  # 顯示：P##y##t##h##o##n

# Example 5.3:

words = ["Python", "is", "awesome"]

text = " ".join(words)

print(text)  # 顯示：Python is awesome

--- --- ---

Ref1: 比較 Python 的格式化字串 — %-formatting、str.format()、 f-string
https://zoejoyuliao.medium.com/%E6%AF%94%E8%BC%83-python-%E7%9A%84%E6%A0%BC%E5%BC%8F%E5%8C%96%E5%AD%97%E4%B8%B2-formatting-str-format-f-string-6d28487ba1d2

Ref2: 如何使用 Python 進行字串格式化

https://blog.techbridge.cc/2019/05/03/how-to-use-python-string-format-method/

Ref3: Python format 格式化函数

https://www.runoob.com/python/att-string-format.html

Ref4: 制霸 Python f-string 各種格式使用方法

https://myapollo.com.tw/blog/python-f-string-formating-syntax/

Ref5: Python String Formatting Best Practices

https://realpython.com/python-string-formatting/

// End.