1. Formatted output
1、%s or %d
%: Represents a placeholder. Note that when % needs to be displayed in the content, add a % before it to escape. For example, if 5% is displayed, then: 5%%
s: represents a string
d: represents the value digital
example:
name = input( ' Please enter your age ' ) age = input( ' Please enter the age ' ) height = input( ' Please input height ' ) msg = " My name is %s, this year is %s, my height is %s, and my learning progress is 3%%s " % (name, age, height) # In 3%%s, the first % is the suffix print (msg )
name = input( ' Please enter name ' ) age = int(input( ' Please enter your age ' )) job = input( ' Please enter a job ' ) hobbie = input( ' your hobby ' ) msg = '''------------ info of %s ----------- Name : %s Age : %d job : %s Hobbie: %s ------------- end ----------------- ''' % ( name, name, age, job, hobbie) # Note that there are two value
print(msg)
2. Initial coding
1. ASCII: 4 binary bits form one byte, one ASCII code occupies one byte
2, Unicode: occupy 4 bytes, too much space.
3. utf-8: an upgraded version of Unicode
Use at least 1 byte to represent English
2 bytes for European text
Occupies 3 bytes to represent Chinese
三、while - else
When the while is interrupted by break, do not go else
Fourth, data conversion
number -- bool value
Non-zero number --> True; zero --> False
True --> 1； False --> 0
Five, logical operation
（）not and or
Operation priority: () > not > and > or
Operation
1. Write code: Calculate the sum of all numbers except 88 in 1 - 2 + 3 ... +(-) 99?
1 # 8. Write the code: Calculate the sum of all numbers in 1 - 2 + 3 ... + 99 except 88? 2 3 count = 1 4 sum = 0 5 while count < 100 : 6 if count == 88 : 7 count = count + 1 8 continue 9 else : 10 if count % 2 == 1 : 11 sum += count 12 else : 13 sum -= count 14 count = count + 1
15 print (sum)
1 #Write code: Calculate the sum of all numbers except 88 in 1 - 2 + 3 ... + (-) 99? 2 3 i = 0 4 j = -1 5 sun = 0 6 while i < 00 : 7 i += 1 8 j = - j 9 if i == 88 : 10 continue 11 else : 12 # j = -j # will The negative sign corresponding to 88 is also skipped, and it is carried over to the next 13 sun = sun + i* j 14 print (sun)
2. The user logs in (three chances to make mistakes) and displays the number of remaining mistakes each time he makes a mistake (hint: use string formatting)
1 username = " yangxiaoer " 2 password = " 123456 " 3 i = 3 4 while i > 0: 5 zh = input( " Please enter your account number: " ) 6 i -= 1 7 if zh == username: 8 mm = input( " Please enter your password: " ) 9 if mm == password: 10 print ( " Authentication successful. Logging in... " ) 11 print (''' Congratulations on your successful login! 12Welcome users to enter 13Username :%s 14Password :%s 15 ''' % (zh, mm)) 16 break 17 else : 18 if i == 0: 19 print ( " Your chance is gone! game over, see you next time! " ) 20 answer = input( ' Try again? Y or N ' ) 21 if answer == ' Y ' : 22 i = 3 23 print(" Wrong password, please re-enter " ) 24 print ( " You still have a chance " +str(i)+ " a chance " ) 25 else : 26 print ( " Please enter the correct username! " ) 27 if i == 0: 28 print ( " Your chance is gone! " ) 29 answer = input( ' Try again? Y or N ' ) 30 if answer == ' Y ' : 31 i = 3 32 print ( " you still have " + str(i) + " a second chance " ) 33 else : 34 print ( ' you TM shameless ' )
