print(3/2) # 此處與C有一定區別，c中兩個整數相除結果也是整數
print("type(3/2) " + str(type(3/2))) # type(3/2)<class 'float'>
print(3.0/2)
print("type(3.0/2) " + str(type(3.0/2))) # type(3.0/2) <class 'float'>
print(3%2) # 求餘
print(3**2) # 9
print(3**3) # 27
print(3**4) # 求3的4次冪 # 81
print(0.1+0.2) # 0.30000000000000004
print("type(0.1+0.2) " + str(type(0.1+0.2))) # type(0.1+0.2) <class 'float'>
print(3*0.1) # 0.30000000000000004
print("type(3*0.1) " + str(type(3*0.1))) # type(3*0.1) <class 'float'>
bicycles = ['trek','cannondale','redline','specialized']
bicycles[0] = 'ducati' # 更改第一個元素
bicycles.insert(0,'first')
bicycles.insert(-1,'倒數第二個') # 在-1處插入數據，新數據會成爲倒數第二個數據
print(bicycles) # ['first', 'ducati', 'cannondale', 'redline', '倒數第二個', 'specialized']
del bicycles[0] # 使用del語句（注意，說的是del語句）刪除某個元素 # 刪除第一個元素
print(bicycles)
#del bicycles[len(bicycles)] #IndexError: list assignment index out of range
# ['ducati', 'cannondale', 'redline', '倒數第二個', 'specialized']
print(bicycles.pop(1)) # 彈出索引爲2的數據： cannondale
print(bicycles.pop(-2)) # 彈出倒數第2個數據："倒數第二個"
print(bicycles) # ['ducati', 'redline', 'specialized']
# 若嘗試彈出越界的數據，將報錯
# print(bicycles.pop(len(bicycles))) # IndexError: pop index out of range
# print(bicycles[len(bicycles)]) # IndexError: list index out of range
# 若嘗試remove()一個不存在的數據，也會報錯
# print(bicycles.remove('honda')) # ValueError: list.remove(x): x not in list
#print(bicycles.remove('不存在'))# ValueError: list.remove(x): x not in list
bicycles.append('b')
bicycles.append('a')
bicycles.append('c')
bicycles.sort() # ['a', 'b', 'c', 'ducati', 'redline', 'specialized']
print(bicycles) # list的sort()方法，會永久改變數組
#bicycles.sort(True) #TypeError: must use keyword argument for key function
bicycles.sort(reverse = True) # 倒序，使用關鍵值傳參
print(bicycles)