Python Road, Day2-python Foundation, list, loop

1. List Exercises
NAME0 = ' Wuchao '
name1 = ' jinxin '
name2 = ' Xiaohu '
name3 = ' Sanpang '
name4 = ' Ligang '

names = "Wuchao jinxin xiaohu sanpang Ligang"
a=[' Wuchao ', ' jinxin ', ' Xiaohu ', ' Sanpang ', ' Ligang ']

#增删改查
#增 slices
print (a[1:]) #取到最后
print (a[1:-1]) #取到倒数第二值
print (a[1:-1:1]) #从左到右一个一个取 "1" is the step size
print (a[3::-2]) #从左到右隔一个取一个

names = [' Alex ', ' Tenglan ', ' Eric ', ' Rain ', ' Amy ']
# a=[' Alex ', ' Tenglan ', ' Eric ', ' Rain ', ' Amy '
print (Names[1:4])
print (names[1:-1])
print (Names[0:3])
print (Names[:3])
print (names[3:])
print (names[3:-1])
print (Names[0::2])
print (Names[0::2])
name = "\n\t Alex li;rain Wang; Jack \ t "
print (name)
print (Name.strip ()) #脱掉, strip girl

Print (Name.split (";")) #分割, divide a character into a list by a space
print (len (name)) #长度

2, increase and revise the search

names = ["Su Haozhi", "Chin", "Li Zhi", "Inflammation Dragon", "full", "liar", "Li Zhi"]
print (names)
print (names[-1])
Print (names.index ("Li Zhi")) #返回元素的索引 \ Subscript
print (Names[3:5]) #0 1 2 3 4 5 6, index 3 to 5 of the previous
Print (names.count ("Li Zhi")) #统计数量
#print (type (names))
names.append ("bald") #默认追加到最后一个
print (names)
#insert插入
Names.insert (4, "Chen Tao") #在索引4饱满之前加一个陈涛
Names.insert (3, "Hongzhiqiang") #在索引3炎龙之前加一个洪智强
print (names)
Print (Names.pop (4)) #删除, delete the last one by default
names.remove ("Li Zhi")
del names[1] #删除
print (names)

3. Notes and Assignments

#!/usr/bin/env python
#_ *_coding:utf-8_*_
__author__ = ' Yu '
Today topic
character encoding
Data Type
Str


Number Type
int integral type
Long Integer type
float
Negative number

BOOL Boolean
true True
false False
character
string Common functions:
Remove whitespace
Split
length
Index
slices

List
Dict
Set

For : else


While : Else


8 4 2 1
1 1 1 1 1 1 1 1 1 1

1024Bytes = 1KB = 1KB
1024KB = 1MD = 1 million bytes = 1 MB
1024MB = 1GB = HD short, 1080P 20 min
1024GB = 1TB
1024TB = 1PB



a binary is the smallest representation unit in a computer.
1 Bytes is the smallest storage unit in a computer

ASCII 256, 8 bits per character
GB2312 1980 67xx
GBK1.0 1995 21000
GB18030 27000

Unicode Universal Code
utf-32 = 4 bytes
utf-16 = 2 bytes

single and double quotes do not have any difference, only for single-line
three-quote single or double quotation marks for multi-line strings, or multiline comments





Job 1
Jump out of the multilayer loop, three-layer cycle, the innermost layer, jumping out of 3 layers,
Job 2
Shopping Cart Program (knowledge points, loops, lists,
)

python shopping.py

Input your salary:5000
you can buy the following things:
1.iphone 5800
2.coffee
3.book
4.condom
>>: 1
can't afford to print, how much is the difference?
>>:2
can afford to put into the shopping cart, deduct money, while printing the balance ... 4970
>>:3
...
>>:4

>>:q
you bought the following things,
Coffee
Book ...
How much money do you have?
Bye

Python Road, Day2-python Foundation, list, loop