day02

while-- keyword (infinite loop)

Format: while condition:

Loop

print(1)
while True:
    print("痒")
    print("鸡你太美")
    print("卡路里")
    print("好运来")
    print("小三")
    print("小白脸")
    print("趁早")
    print("过火")
print(2)

falg = True
while falg:
  print(1)
print(2)


# 正序的示范
count = 1
while count <= 5:
    print(count)
    count = count + 1

# 倒序的示范
count = 5
while count:
    print(count)
    count = count - 1

# 正序打印  25 - 57
count = 25
while count < 58:
    print(count)
    count = count + 1


# 倒序打印  57 - 25
count = 57
while count > 24:
    print(count)
    count = count - 1

Digital is non-zero is zero False True

# print(bool(0))
# 数字中非零的都是True

break: terminate the loop, break the following code will not be executed

while True:
    print(123)
    print(234)
    break   # 终止当前循环，break下方的代码不会进行执行
    print(345)
print(1111)

continue: the end of the cycle, a direct jump to the next cycle (the last line of the loop body disguised), the following code will not be executed

while True:
    print(123)
    print(234)
    print(345)

while True:
    print(123)
    print(234)
    continue
    #continue 伪装成循环体中的最后一行代码(跳出当前循环继续下次循环)
    #continue 下面的代码不会执行
    print(345)
print(1111)

while else: an overall (cycle), when the condition is satisfied when not performed, when the execution condition is not satisfied

while True:
    print(111)
    break
else:
    print(222)

while True:
    print(111)
    break
print(222)

# while   else
# 0.退出
# 1.开始登录
# 如果用户选择序号0就提示用户退出成功
# 如果用户选择序号1就让用户输入用户名和密码然后进行判断，正确就终止循环，错误就重新输入
srr = """
0.退出
1.开始登录
"""
print(srr)
num = int(input("请输入你要的数字："))
while num == 1:
    name_input = input("请输入你的用户名：")
    password_input = input("请输入你的密码：")
    name = "alex"
    password = "123"
    if name_input == name and password_input:
        print("登录成功")
        break
    else:
        print("用户名或者密码错误，请重新输入！")
else:
    print("退出成功")

to sum up:
- Break the cycle way:
  1. Make changes to conditions
  2. break

break - break the current cycle (terminate the current cycle)
1. continue - out of the current cycle continues for the next cycle (the last line of code disguised continue loop body)
2. break and continue in common: they do not execute the following code

String formatting

a = "------------- info -------------"
b = "name:"
c = "age:"
d = "job:"
e = "-------------- end -------------"
name = input("name")
age = input("age")
job = input("job")
print(a + "\n" + b + name + "\n" + c + age + "\n"+ d + job + "\n" +e)

% Is a placeholder
%% (escape) escape into ordinary%
% S is a string type of accounting position
% D are numbers representing the type of location

Order of delivery location, occupancy, and fill bits must correspond to

s = """ ------------- info -------------
name:%s
age:%s
job:%s
-------------- end -------------
"""
name = input("name")
age = int(input("age"))
job = input("job")
print(s%(name,age,job))

# num = input("学习进度：")
# s = "大哥黑的学习进度为：%s%%"
# print(s%(num))

# num = input("学习进度：")
# num1 = input("aaaa：")
# s = "大哥黑的学习进度为：%s%"
# print(s%(num,num1))

# num = input("学习进度：")
# num1 = input("aaaa：")
# s = "大哥黑的学习进度为：%s%s"
# print(s % (num, num1))

Extended: f "{variable name} {string}" version 3.6 and above to use

# s = f"今天下雨了{input('>>>')}"
# print(s)

# s = f"大黑哥的学习进度为{input('<<<')}"
# # print(s)

# s = f"{1}{2}{3}"
# print(s)

Operators

Arithmetic Operators

/ Addition ( {result} 5/2 result python2 is an integer, a decimal result python3)
// divisible (except flooring)
** power (power)
% Modulus (remainder)

Comparison Operators

--- >
--- <
--- ==
--- !=
--- >=
--- <=

Assignment Operators

= Assignment
+ = From Canada
- = Decrement
* = Squared
/ = From the addition
//=
**=
%=

Logical Operators

and (with): the truth the whole truth,

We are really behind and take the time value
Are taken and the previous value is false when
Shinichi take a fake false value

# print(3 and 4)
# print(0 and 4)
# print(0 and False)

# print(3 and 5 and 9 and 0 and False)
# print(5 and False and 9 and 0)
# print(1 and 2 and 5 and 9 and 6)

or (or): it is a true true
- Are true when the previous value or take
- We have taken back or false value when
- A really really worth taking a fake
```
# print(1 or 0)
# print(1 or 2)
# print(0 or False)
# print(1 or 9 or 4 or 0 or 9)
```
not (non): opposition

# print(not False)

级别：（）> not > and > or

Sequence: from left to right execution

# print(9 and 1 or not False and 8 or 0 and 7 and False)

Member operator

in: there is
not in: does not exist

# s = "alexdsb"
# if "sb" not in s:
#     print(True)
# else:
#     print(False)

The initial coding

Code set (codebook)

# 今 0101
# 天 0110
# 晚 0010
# 上 0001
# 去 1001
# 便 1000
# 利 0100
# 店 1111
#
#
# 00000101  00000110  0010000110011001

ascii (United States): Does not support Chinese
GBK (National Standards codebook): English 8 bits (1 byte), Chinese 16 bits (2 bytes)
unicode (Unicode): English 16 (2 bytes), Chinese 32-bit (4-byte)
utf-8 (variable length coding, the most popular): English 8 bits (1 byte), text Europe 16 (2 bytes), Asian 24 bits (3 bytes)
linux system - utf-8
mac System - utf-8
windows system - gbk
Unit conversion:
- A byte (1Bytes) = 8 bit (8bit)
- 1024Bytes = 1KB
- 1024KB = 1MB
- 1024MB = 1GB
- 1024GB = 1TB common
- 1024TB = 1PB
- 1024PB = 1EB

day02_ million annual salary into the second day of