python第八课：字典的魔法+练习题

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# 字典
# dict
#  info = {"k1":"v1","k2":"v2","k3":True,"k4":[11,22,33],"k5":()}
#  1可以嵌套，value 可以是任何值

# 2布尔值(0,1)，列表、字典不能作为字典的key
# info = {
#     1:"asdf",
#     "k1":"adadf",
#     True:"123",
#     (11,22):345
# }
# print(info)


# 3字典是无序的。打印出来的时候顺序不一定。
# 取值的时候中括号中参数加上key即可。
# 通索引方式找到指定元素
# v = info["k3"][2]["sd"]
#
# 4删除字典中的某一个键值对
# del info["k1"]
# del info["k3"][3]
# print(info)


# 5for循环，默认for循环只有key
# for item in info:
#     print(item)
#
# 6加上参数可以获取value或者只有获取value
# for item in info.values():
#     print(item,info[item])
# for item in info.keys():
#     print(item,info[item])
# --------------------------------
# for k,v in info.items():
#     print(k,v)


# 字典特有的相关操作：
#
# 1、根据序列来创建字典，并给统一的值
# fromkeys

# dic = {
#     "k1":"v1"
# }
# v = dict.fromkeys(["k1",124,"888"],124)
# print(v)



# 2、取值：
# dic.get("k1")
# get 的方式如果key不存在时，系统不会报错，可以指定默认值，none
#
#
# 3、删除并获取值
# dic.pop
# dic.popitem()

#
# 4、设置值，如果已经存在就是获取当前key对应的值，
# 如果不存在就进行添加设置。
# dic.setdefault("key","value")
#
#
# 5、更新
# 如果存在即更新
# 如果不存在就添加
# dic.update
#
# dic.update(k1=124,k3=345,k5="adfadf")#或者在括号中用“:”来标识键值对
#
#
# 6、keys()
# 7、values()
# 8、items()  get()  update
#
#
# ############整理############必须要会的
# 1、数字
# int(..) ,
#
#2、 字符串
# replace/find/join/strip/startswith/split/upper/lower/format
# tempalte = "i am {name},age:{age}"
# v = tempalte.format(name="alex",age=19)
# v = tempalte.format({**"name":"alex","age":19})
# print(v)

3、列表
append/extend/insert/
索引、切片、循环

4、元组
索引、切片、循环  以及元素不能被修改


5、字典
get/update/keys/values/items
for,索引,in    默认是查询key


6、布尔值
0  1
bool（）
None "" ,(), [],{},0  =>Fals


-----------------------------------------------
练习题

#!/usr/bin/env python
# -*- coding:utf-8 -*-
# l = [11,22,33,44,55,66,77,88,99,90]
# result = {}
# # {'k1': [77, 88, 99, 90], 'k2': [11, 22, 33, 44, 55]}
#
# for item in l:
#     if item < 66:
#         # result.update({"k1": item}) # {'k1':11}
#         # {'k1': [11,22]}
#         if "k1" not in result:
#             result['k1'] = [item, ]    # {'k1': [11,]}
#         else:
#             result['k1'].append(item)
#     elif item > 66:
#         if "k2" not in result:
#             result['k2'] = [item, ]    # {'k1': [11,]}
#         else:
#             result['k2'].append(item)



# for i in l:
#     if i < 66:
#         a.append(i)
#     if i > 66:
#         b.append(i)
# print({'k1':b,'k2':a})


# 有两个列表
# l1   =  [11,22,33]
# l2   =  [22,33,44]
# a.    获取内容相同的元素列表
# b.    获取 l1  中有， l2 中没有的元素列表
# c.    获取 l2  中有， l1 中没有的元素列表
# d.    获取 l1  和 l2   中内容都不同的元素
l1 =  [11,22,33]
l2 =  [22,33,44]
# for i in l2:
#     if i not in l1:
#         print(i)
# for i in l2:
#     if i not in l1:
#         print(i)
count =0

for i in range(1, 9):
    for v in range(1, 9):
        if i !=v:
            count += 1
# count = count -8
print(count)
#
# count =0
# ls = [3,5,8,9]
# for i in range(0, len(ls)):
#     for v in range(0, len(ls)):
#         if i !=v:
#             count += 1
# # count = count -8
# print(count)

#99乘法表
# for i in range(1,10):
#     string = ""
#     for j in range(1,i+1):
#         string +=str(j) + " * "+str(i) + " = " +str(i*j)+"\t"
#     print(string)

# print("aaa",end="")
# print("bbb")

# for i in range(1,10):
#     for j in range(1,i+1):
#         print(str(j) + " * "+str(i) + " = " +str(i*j)+"\t",end="")
#     print("\n",end="")

# for i in range(1,10):
#     for j in range(1,i+1):
#

# \n
# print('alex', end='SB')
# print('alex')
# print('alex','haifeng','gangniang',sep='搞')
# 这里面的数字两个组合 多少种不同样的，数字不重复的
# li = [1,2,3,4]
# l =len(li)
# for i in range(0,l-1):
#     for v in range(i+1,l):
#         print(li[i],li[v])
# for x in range(1,100//5):
#     for y in range(1,100//3):
#         for z in range(1,100):
#             if x + y + z == 100 and 5*x + 3*y + z/3 == 100:
#                 print(x,y,z)


# li = ['alex','eric',123]
# li[2] = str(li[2])
#
#
# v = "_".join(li)
# print(v)
# tu = ('alex', 'eric', 'rain')
# print(len(tu))
# print(tu[2])
# print(tu[1:])
# #step 为正
# print(tu[1:90])
# for elem in tu:
#     print(elem)
# for idx in range(len(tu)):
#     print(idx)

# for idx, elem in enumerate(tu, 10):
#     print(idx, elem)
# tu =(
#     "alex",
#     [
#         11,
#         22,
#         {
#             "k1":'v1',
#             "k2":["age","name"],
#             "k3":(11,22,33)
#         },
#         44
#     ]
# )
# tu[1][2]["k2"].append("")


# nums = [2,7,11,15,1,8,7]
# a =[]
# for i in range(len(nums)):
#     for j in range(len(nums)):
#         if nums[i] + nums[j] ==9:
#             a.append((i,j,))
# print(a)

# li = ["sdsdsd"]
# print (len(li))
# li.append("dsad")
# li.insert(0,"dsad")
# li.remove("eric")
# v = li.pop(1)
# print(li,v)
#
# v = li.reverse()
# for i in range(len(li)):
#     print(i)
# for i,q in enumerate(li,100):
#     print(i,q)
# for i in li:
#     print(i)

# user_list = [
# ]
# for i in range(1,302):
#     temp = {'name': 'alex'+str(i), 'email': 'alex@lve.com' + str(i), 'pwd': 'pwd'+str(i)}
#     user_list.append(temp)
#
# while True:
#     # 每页显示10条数据
#     s = input("请输入1,2,3-31页码：")
#     s = int(s)
#     # user_list[0,10]  1
#     # user_list[10,20]  2
#     # user_list[20,30]  3
#     start = (s-1) * 10
#     end = s * 10
#     result = user_list[start: end]
#     for item in result:
#         print(item,type(item))

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