Python's for,while and if

Python's loop and Judge authentication account and password

ImportGetpass#Import Moduleusername= Input ('Username:') Password= Getpass.getpass ('Password:')#Enter password not displayedUser Password Authentication: if and Else#Author:yao XiaodongImportGetpass_username=' Arthur'_password='123456'username= Input ('Username:') Password= Input ('Password:') if_username = = Username and_password = =Password:Print('Welcome {name} to Python world'. Format (name=username))Else:    Print('Auth filed')

Guessing age while way

#While LoopAuthur_age = 500Count=0 whileCount < 3: Guess_age= Int (Input ('Guess_age:'))    ifGuess_age = =Authur_age:Print('Yes,you is right!')         Break    elifGuess_age >Authur_age:Print('It 's to bigger ...')    Else:        Print('It 's to smaller ...') Count+ = 1Else:    Print(' Error')

For way

For Loop Authur_age= 500 forIinchRange (3): Guess_age= Int (Input ('Guess_age:'))    ifGuess_age = =Yxd_age:Print('Yes,you is right!')         Break    elifGuess_age >Yxd_age:Print('It 's to bigger ...')    Else:        Print('It 's to smaller ...')Else:    Print(' Error')

While+if judge whether to continue after three times

Age = 21Count=0 whileCount < 3: Guess_count= Int (Input ("Guess_count:"))    ifGuess_count = =Age :Print('Yes')
Break
    elifGuess_count >Age :Print('Big')    Else:        Print('Small') Count+ = 1ifCount = = 3: Paly= Input ('Do you want paly Agen? (y/n):')        ifPaly = ='y': Count=0elifPaly = ='N':            Print(' All right')
        Else:            Print('(y/n) Do you know?')

What is the difference between break and continue?

Different points

Break jumps out of the loop, and if a break is encountered in the loop, the loop is directly invalid.

Continue jumps out of the current loop, if the loop encounters a continue, jump out of the loop to continue the next loop.

Same point:

Break and continue all only jump out of the current loop, that is, if the for loop is a for loop, it will only jump out of the for loop where the break or continue is located. As an example:

For example:

 forIinchRange (3):    Print('---------'I'-------')     forNinchRange (3):        ifn >1:Print(n)Else:             Break#run the result as---------0----------------1----------------2-------
#也就是说遇到了break后整个循环都没有了结果, but the outer loop has no effect

Look at continue again.

 forIinchRange (3):    Print('---------'I'-------')     forNinchRange (3):        ifn > 1:            Print(n)Else:            Continue#run the result as---------0-------2---------1-------2---------2-------2
#也就是说continue只是跳出一次循环, not the whole cycle,

But the outer loop has no effect.

Python's for,while and if