list_a = []  # 空列表，即len(list_a) == 0
list_b = [2018, 10, '2018-10-1', ['hi', 1, 2], (33, 44)]

# list_b 長度為5，包含2個數字元素、1個字符串元素、1個列表元素和1個元組元素
len(list_b) == 5
list_b[0] == list_b[-5] == 2018
lits_b[3] == list_b[-2] == ['hi', 1, 2] 
lits_b[4] == list_b[-1] == (33, 44)

list_a = [1, 2, 3]
list_b = list("abc") # list_b == ['a', 'b', 'c']
list_c = list((4, 5, 6)) # list_c == [4, 5, 6]
list_d = [i for i in list_a] # list_d == [1, 2, 3]
list_e = [i*j for i in list_a for j in list_c] # list_e == [4,5,6,10,12,12,15,18]
list_f = [i*j for i,j in zip(list_a,list_c)] # list_f == [4, 10, 18]
list_g = [i for i in list_a if i%2 == 0] # list_g == [2]

# 結合range()函數，range(start, stop[, step])
list_h = list(range(3)) # list_h == [0, 1, 2]
list_i = list(range(3,7)) # list_i == [3, 4, 5, 6]
list_j = list(range(3,9,2)) # list_j == [3, 5, 7]

# 找出100以內的能夠被3整除的正整數
list_k = list(range(3,100,3)) # list_k == [3, 6, 9, ..., 96, 99]

# 以下分別添加2個元素
list_a = []
list_a.append('happy') # list_a == ['happy']
list_a.insert(0, 'very') # list_a == ['very', 'happy']

# 以下兩種擴充列表方式
list_1 = ['I', 'am']
list_2 = ['very', 'happy']
list_3 = list_1 + list_2 # 新列表 list_3 == ['I', 'am', 'very', 'happy']
list_1.extend(list_2) # 原列表1擴充，list_1 == ['I', 'am', 'very', 'happy']

# 以下4種刪除列表元素方式
list_1 = list_2 = list_3 = list_4 = ['I', 'am', 'very', 'happy']
del list_1[0] # list_1 == ['am', 'very', 'happy']
list_2.remove('I') # list_2 == ['am', 'very', 'happy']
list_3.pop() # list_3 == ['I', 'am', 'very']
list_4.pop(0) # list_4 == ['am', 'very', 'happy']

# 清空與銷毀
list_a = [1, 2, 3]
list_b = [1, 2, 3]
list_b.clear()  # list_b == []
del list_a  # 沒有l(wèi)ist_a了，再使用則會報錯

li = [1, 4, 5, 6, 7, 9, 11, 14, 16]

# 以下寫法都可以表示整個列表，其中 X >= len(li)
li[0:X] == li[0:] == li[:X] == li[:] == li[::] == li[-X:X] == li[-X:]

li[1:5] == [4,5,6,7] # 從1起，取5-1位元素
li[1:5:2] == [4,6] # 從1起，取5-1位元素，按2間隔過濾
li[-1:] == [16] # 取倒數第一個元素
li[-4:-2] == [9, 11] # 從倒數第四起，取-2-(-4)=2位元素
li[:-2] == li[-len(li):-2] == [1,4,5,6,7,9,11] # 從頭開始，取-2-(-len(li))=7位元素

# 注意列表先翻轉，再截取
li[::-1] == [16,14,11,9,7,6,5,4,1] # 翻轉整個列表
li[::-2] == [16,11,7,5,1] # 翻轉整個列表，再按2間隔過濾
li[:-5:-1] == [16,14,11,9] # 翻轉整個列表，取-5-(-len(li))=4位元素
li[:-5:-3] == [16,9] # 翻轉整個列表，取-5-(-len(li))=4位元素，再按3間隔過濾

li[::0] # 報錯（ValueError: slice step cannot be zero）

list_1 = [2018, 10, '2018-10-1', ['hi', 1, 2], (33, 44)]
len(list_1) == 5
list_1.count(10) == 1 # 元素10的數量為1
list_1.index(10) == 1 # 元素10的索引為1
list_1.reverse() # list_1 == [(33, 44), ['hi', 1, 2], '2018-10-1', 10, 2018]

# 比較淺拷貝與深拷貝
import copy
list_a = [2018, 10, '2018-10-1', ['hi', 1, 2], (33, 44)]
list_b = ['hi', 1, 2]
list_c = list_a.copy() # list_c == [2018, 10, '2018-10-1', ['hi', 1, 2], (33, 44)]
list_d = copy.deepcopy(list_a) # list_d == [2018, 10, '2018-10-1', ['hi', 1, 2], (33, 44)]

# 改變原列表中的可變對象元素
list_a[3].append('new') # list_a == [2018, 10, '2018-10-1', ['hi', 1, 2, 'new'], (33, 44)]

# 淺拷貝中的可變對象會隨原列表變化而變化
list_c == [2018, 10, '2018-10-1', ['hi', 1, 2, 'new'], (33, 44)]

# 深拷貝中的可變對象不會隨原列表變化而變化
list_d == [2018, 10, '2018-10-1', ['hi', 1, 2], (33, 44)]

# 比較sort() 與 sorted()
list_1 = list_2 = [2,1,4,6,5,3]
list_1.sort() # 原列表變化：list_1 == [1,2,3,4,5,6]
list_3 = sorted(list_2) # 原列表不變：list_2 == [2,1,4,6,5,3]; list_3 == [1,2,3,4,5,6]

# 計算斐波那契數列的生成器
def fibon(n):
a = b = 1
for i in range(n):
yield a # 使用yield
a, b = b, a + b

# 計算前1000000個數，通過next()函數，按順序每次生成一個數
g = fibon(1000000)
next(g) # 1
next(g) # 1
next(g) # 2
next(g) # 3
next(g) # 5
# 以此類推，但若調用超過1000000次，就會報異常StopIteration

# 計算前1000000個數，通過for循環(huán)逐一打印生成數
for x in fibon(1000000):
print(x)

l = [x*2 for x in range(5)] # 列表生成式，4以內整數的2倍數
g = (x*2 for x in range(5)) # 生成器表達式
type(l)  # 結果：<type 'list'>
type(g)  # 結果：<type 'generator'>

print(l) # 結果：[0,2,4,6,8]
print(g) # 結果：<generator object at 0x000002173F0EBC50>
next(g)  # 0
next(g)  # 2
next(g)  # 4
next(g)  # 6
next(g)  # 8
next(g)  # Traceback (most recent call last): ....StopIteration

for x in g:
print(x, end=' ') # 結果：0 2 4 6 8