Python 8天从入门到精通训练营 -
数据类型-字典来啦
先在excel表里面
姓名， 年龄，座位号，身高，编辑出来，然后ctrl + E ，来生成一组。
|
student1
|
15
|
seat1
|
158
|
["student1",15,"seat1",158],
|
|
student2
|
16
|
seat2
|
159
|
["student2",16,"seat2",159],
|
|
student3
|
17
|
seat3
|
160
|
["student3",17,"seat3",160],
|
|
student4
|
18
|
seat4
|
161
|
["student4",18,"seat4",161],
|
|
student5
|
19
|
seat5
|
162
|
["student5",19,"seat5",162],
|
|
student6
|
20
|
seat6
|
163
|
["student6",20,"seat6",163],
|
|
student7
|
21
|
seat7
|
164
|
["student7",21,"seat7",164],
|
|
student8
|
22
|
seat8
|
165
|
["student8",22,"seat8",165],
|
|
student9
|
23
|
seat9
|
166
|
["student9",23,"seat9",166],
|
|
student10
|
24
|
seat10
|
167
|
["student10",24,"seat10",167],
|
student_list = [
["student1",15,"seat1",158],
["student2",16,"seat2",159],
["student3",17,"seat3",160],
["student4",18,"seat4",161],
["student5",19,"seat5",162],
["student6",20,"seat6",163],
["student7",21,"seat7",164],
["student8",22,"seat8",165],
["student9",23,"seat9",166],
["student10",24,"seat10",167]
]
#####命令#####
student_list = [
["student1",15,"seat1",158],
["student2",16,"seat2",159],
["student3",17,"seat3",160],
["student4",18,"seat4",161],
["student5",19,"seat5",162],
["student6",20,"seat6",163],
["student7",21,"seat7",164],
["student8",22,"seat8",165],
["student9",23,"seat9",166],
["student10",24,"seat10",167]
]
print(student_list)
print(student_list[0:])
print(student_list[0:-1])
print(i[-4:-1])
print(i[-1])
###输出结果####
"C:\Program Files\Python310\python.exe" "C:/Python/python8天从入门到精通/Day3/3.5 数据类型字典来了.py"
[['student1', 15, 'seat1', 158], ['student2', 16, 'seat2', 159], ['student3', 17, 'seat3', 160], ['student4', 18, 'seat4', 161], ['student5', 19, 'seat5', 162], ['student6', 20, 'seat6', 163], ['student7', 21, 'seat7', 164], ['student8', 22, 'seat8', 165], ['student9', 23, 'seat9', 166], ['student10', 24, 'seat10', 167]]
[['student1', 15, 'seat1', 158], ['student2', 16, 'seat2', 159], ['student3', 17, 'seat3', 160], ['student4', 18, 'seat4', 161], ['student5', 19, 'seat5', 162], ['student6', 20, 'seat6', 163], ['student7', 21, 'seat7', 164], ['student8', 22, 'seat8', 165], ['student9', 23, 'seat9', 166], ['student10', 24, 'seat10', 167]]
[['student1', 15, 'seat1', 158], ['student2', 16, 'seat2', 159], ['student3', 17, 'seat3', 160], ['student4', 18, 'seat4', 161], ['student5', 19, 'seat5', 162], ['student6', 20, 'seat6', 163], ['student7', 21, 'seat7', 164], ['student8', 22, 'seat8', 165], ['student9', 23, 'seat9', 166]]
Process finished with exit code 0
======================================================
student_list = [
["student1",15,"seat1",158],
["student2",16,"seat2",159],
["student3",17,"seat3",160],
["student4",18,"seat4",161],
["student5",19,"seat5",162],
["student6",20,"seat6",163],
["student7",21,"seat7",164],
["student8",22,"seat8",165],
["student9",23,"seat9",166],
["student10",24,"seat10",167]
]
Python 8天从入门到精通训练营
# print(student_list)
# print(student_list[0:])
# print(student_list[0:-1])
# for i in student_list:
# # print(i[0:-1])
print(student_list[-4:-1])
print(student_list[-1])
print()
print(student_list[0])
print(student_list[0][0])
print(student_list[0][1])
print(student_list[0][2])
"C:\Program Files\Python310\python.exe" "C:/Python/python8天从入门到精通/Day3/3.5 数据类型字典来了.py"
[['student7', 21, 'seat7', 164], ['student8', 22, 'seat8', 165], ['student9', 23, 'seat9', 166]]
['student10', 24, 'seat10', 167]
['student1', 15, 'seat1', 158]
student1
15
seat1
Process finished with exit code 0
"C:\Program Files\Python310\python.exe" "C:/Python/python8天从入门到精通/Day3/3.5 数据类型字典来了.py"
[['student7', 21, 'seat7', 164], ['student8', 22, 'seat8', 165], ['student9', 23, 'seat9', 166]]
['student10', 24, 'seat10', 167]
['student1', 15, 'seat1', 158]
student1
15
seat1
Process finished with exit code 0
===========================
命令：
dic = {}
print(dic)
输出：
{}
=================== 2022-12-08 13：44-
dic = {
"s1":["student1",15,"seat1",158],
"s2":["student2",16,"seat2",159],
"s3":["student3",17,"seat3",160]
}
print("s1" in dic)
命令：
dic = {
"s1":["student1",15,"seat1",158],
"s2":["student2",16,"seat2",159],
"s3":["student3",17,"seat3",160]
}
print("s1" in dic)
输出：
True
===================
存复杂的信息，然后快速的查询，这个就是字典的好处。
key value ，value后面可以跟任何值，跟一个字典都可以。
key必须是字符串或者数字。 字符串和数字是不可变的。 key还必须是唯一的。
value可以重复。
字典是没有顺序的。
命令：
dic = {
"s1":["student1",15,"seat1",158],
"s2":["student2",16,"seat2",159],
"s2":["student",1,"seat",1],
"s3":["student3",17,"seat3",160]
}
print("s1" in dic)
print(dic["s2"]) ##输出key是s2的value。 key是重复的，第2个出来会把第一个覆盖。所以key要唯一。
输出：
True
['student', 1, 'seat', 1]
字典的好处在于，有一个值，还是一亿个值，查询的速度几乎一样。 很神奇。 这就是算法的魅力。算法工程师就是解决效率的问题。
下一节，学习字典的增删改查。
