Python Basic & conditional statements

Base: 1. The first sentence of Python usage

• Python does not limit the suffix name, it can be arbitrary
• When importing a module, if it is not a. py file (the file suffix later is py)

Usage of 2.input:

• Wait forever until the user enters a value. The input value will be assigned to one thing.

3. Variable Name:

• -Alphabet
• -Digital
• -Underline

PS: numbers cannot begin; It is not a keyword; it's best not to repeat what Python has built-in

Keywords: [' and ', ' as ', ' assert ', ' Break ', ' class ', ' Continue ', ' Def ', ' del ', ' elif ', ' Else ', ' except ', ' exec ', ' finally ', ' for ' , ' from ', ' global ', ' if ', ' Import ', ' on ', ' is ', ' lambda ', ' no ', ' or ', ' pass ', ' print ', ' raise ', ' return ', ' try ', ' while ', ' with ', ' yield ']

For example:

1 " Welcome to your arrival!  "    #变量 2Print(A1)3 ===========4print( " Welcome to your arrival. ")

4. Conditional Statements

• If condition (code block at one level after a conditional statement)

1 if Conditions: 2     Print ("OK") 3 Else : 4     Print ("Error")

• If nesting

1 if1=1:2     if2=2:3         Print("Hello")4         Print("Hello2")5     Else:6         Print("Error")7 Else:8     Print("Error2")

• If elif multi-condition judgment

1INP = input ('Please enter your membership level:')2 ifINP = ="Senior Member":3     Print('Welcome to Senior members')4 elifINP = ="Platinum Members":5     Print('Welcome Platinum Members')6 elifINP = ="Diamond Members":7     Print('Welcome Diamond Members')8 Else:9     Print('Welcome to Ordinary members')Ten Print('Welcome to our store ...')

Knowledge Points: If basic statement Else

Add: Pass means empty code, meaningless; only used to represent blocks of code. If Python does not want to output anything, the write pass skips directly without outputting any statements.

5. Basic data types

• String (quotation marks):

1 " Alex " 2 ' Alex ' 3 """ Alex """ 4 " " Alex " "

How to use the string:

1 addition:2N1 ='Alex'3N2 ='Tom'4N3 = n1+N25 Print(N3)#Output Effect Alextom6 7 multiplication:8N1 ='Alex'9N2 = n1*10Ten Print(N2)#Output Effect Alexalexalexalexalexalexalexalexalexalex

• Digital:

1 eg:2Age = 193 4 Add, subtract, multiply, divide, Zhifang, take surplus:5A1 = 106A2 = 207a3 = A1 +A28a3 = A1-A29a3 = A1 *A2TenA3 = 100/10 OneA3 = 3**4#get 3 of the 4-time Square Aa3 = 39% 8#get 39 divided by 8 to get the remainder -A3 = 39//8#get 39 divided by 8 to get the quotient -  the judging odd and even numbers; -A = 15 -temp = a% 2 - iftemp = =0: +     Print('even') - Else: +     Print('Odd')

6. Cycle

• Dead Loop:

 1  import   time  2  while  1 = = 1 :  3  print  (   ok  , Time.time ()) 

1 Import  Time 2 count = 03 while Count <:4     print( Count)5     #count =6     count = count + 17  Print(123)

Ps:

1.while .... else loop

2.continue terminates the current loop and begins the next cycle; Break terminates so loop

Python Basic & conditional statements