a = 3

a = 3
a = "hello"

print("取商:", 5 // 2)
print("取餘:", 5 % 2)
print("次方:", 5 ** 2)
print("相等:", 2 == 2)
print("取整數:", int(5.2))
print("換成編碼:", ord("A"))
print("換成字母:", chr(66))
print("二進位:", bin(4))
print("八進位:", oct(10))
print("十六進位:", hex(25))
print("轉換十進位:", int("100", 2))
print("絕對值:", abs(-2.4))

import math
print("取天花板:", math.ceil(2.4))
print("取地板:", math.floor(2.4))
print("取階乘:", math.factorial(3))
print("最大公因數:", math.gcd(6, 8))

a = "hello"

a = "hellopython"
print("取第三個:", a[2])
print("取第三到第五個:", a[2:5])
print("跳號:", a[2:5:2])
print("反向:", a[::-1])
print("算長度:", len(a))
print("相等:", a == "hello")
print("一部分:", "hel" in a)
print("重複:", a * 3)

a = "Hello" * 3
print("完全取代:", a.replace("Hello", "bye"))
print("部分取代:", a.replace("Hello", "bye", 1))
print("轉換小寫:", a.lower())
print("轉換大寫:", a.upper())
print("組合:", "-".join(["2019", "10", "16"]))
print("分割:", "2019-10-16".split("-"))
print("是否是我要的開頭:", a.startswith("Hel"))
print("是否是我要的結尾:", a.endswith("lo"))

a = [3, 1, 2]
b = [3, 1, 2]
print("合併:", a + b)
print("重複:", a * 3)
print("相等:", a == b)
print("是否在裡面:", 3 in a)
print("長度:", len(a))
print("排序:", sorted(a))
print("排序(反):", sorted(a, reverse=True))
print("反向:", a[::-1])
del b[0]
print("刪除後:", b)

a = ["cat", "dog", "elephant"]
a.append("lion")
print("加到最後:", a)
b = a.pop()
print("丟掉最後:", a)
print("丟出東西:", b)
a.insert(1, "tiger")
print("加入到固定位置:", a)
a.remove("cat")
print("移除:", a)
a.reverse()
print("相反:", a)
a.sort()
print("排序:", a)

a = ["cat", "lion", "dog"]
for e in a:
    print("標準迴圈:", e)

for i, e in enumerate(a):
    print("座號:", i, "物品:", e)
    
b = [20, 30 ,50]
for e1, e2 in zip(a, b):
    print("物品1:", e1, "物品2:", e2)

result = 0
for i in range(10):
    result = result + (i + 1)
    print("目前累積:", result)

set1 = {3, 1, 2 ,5}
set2 = {6, 2, 1, 4}
print("交集:", set1 & set2)
print("聯集:", set1 | set2)
print("差集:", set1 - set2)

set1 = {3, 1, 2, 5}
set1.add(6)
print("加入東西後:", set1)
set1.discard(5)
print("丟掉東西後:", set1)

dict1 = {"name":"Elwing", 
         "height":175, 
         "weight":75}
dict1["height"] = dict1["height"] + 5
print("字典:", dict1)

dict1 = {"name":"Elwing", 
         "height":175, 
         "weight":75}

for k in dict1.keys():
    print("名字:", k)

for v in dict1.values():
    print("值:", v)
    
for k, v in dict1.items():
    print("名字:", k, "值:", v)

# 創造一個 tuple
person = ("Elwing", 175, 75)
# 兩個tuple相加, 注意tuple裡如果只有一個東西, 必須在最後放一個,
person = person + ("Taipei", )
# tuple支援所有的位置操作
print(person[-1])
# tuple內建不支援刪除操作, 因為python假定你只是在短暫的時間使用
# 但要做還是可以改用加法做(建議不要)
print(person[:2] + person[3:])