lesson_2 常用数据类型

# 列表      [ ]     索引取值：取下不取上

# 可重复
list_1 = [1,2,3]
list_2 = ["蟹老板","章鱼哥","海绵宝宝",True,list_1,"蟹老板"]       
print(list_2)
print(list_2)
# 有序
print(list_2[0])
print(list_2[2])
print(list_2[-1])
print(list_2[0:4])
print(list_2[:-3])
print(list_2[2:])
print(list_2[:])
print("=============")
print(list_2[-2][1])     # 取两层列表的值
# 获取长度
list_len = len(list_2)
print(list_len)
# 取最后一个值  -- 通过长度
print(list_2[list_len - 1])
# 添加值
list_2.append("蛋清")
# 插入
list_2.insert(1,"蛋黄")
print(list_2)
# 修改值
list_2[3] = False
print(list_2)
# 删除值
list_2.remove(list_1)
list_2.remove("蟹老板")
print(list_2)
# 删除所有
# list_2.clear()
# print(list_2)      # --> []
list_3 = ["尤加利","露莲"]
print(list_2 + list_3)
print(list_3 + list_2)
print(list_3*2)

print(a.swapcase())   # 大小写互换
print(a.lower())      # 大写变小写
print(a.upper())      # 小写变大写

 

# 字典    {}    键名一般为字符串，且不能重复

DongDong = {"name":"东东","age":28,"height":188,"sex":"男","mood":"happy"}
# 无序
print(DongDong)
print(DongDong)
# 读取数据
print(DongDong["height"])
print(DongDong.get("height"))
# 修改数据
DongDong["name"] = "大东"
print(DongDong)
# 增加数据 -- 键值对
DongDong["study"] = "Java"
print(DongDong)
# 获取字典的长度
print(len(DongDong))
# 字典组合
NianNian ={"who":"念念","like":"shutterbug"}
DongDong.update(NianNian)
print(DongDong)

# 在列表里的字典里添加一个值
# 第一种
list_last = ["hello","python",{"sex":"girl"}]
print(list_last)
list_last[-1]["name"] = "拍打星"
print(list_last)
# 第二种
B = list_last[-1]
B["name"] = "拍打星"
print(list_last)
print(B)
# 第三种
A = [1,3,5,"哈哈"]
dict_A = {"hello":"你好"}
A.append(dict_A)
dict_A["嘿"] = "你好"
print(A)
# id 为内存地址  这个与下面不一致
print(id(A))
# 下面两个的id 是一致的
print(id(dict_A))
print(id(A[-1]))
# 下面的内存地址 都一致
a = 1
b = a
c = b
d = 1
e = c
print(id(a))
print(id(b))
print(id(c))
print(id(d))
print(id(e))

# 字典组合
# 第一种
B = {"name":"xiaojian","age":28,"is_marry":False}
print(B)
C ={"role":"teacher","class":"tescher"}
B.update({"role":"teacher","class":"tescher"})
print(B)
# 第二种
D = dict(B,**C)     # dict(B,**C)是两个字典组合
print(D)

# 获取字典value里的列表添加某一个值
print("---------------------")
E = {"role":"teacher","class":"tescher","hobby":["chifan","wan"]}
print(E)
E["hobby"].append("sleep")
print(E)

  # 元祖  （）   有序   只读   不能增删改  不能二次赋值