how to create a lock in the code

Question

if the wrong note is typed twice and it goes to the second note

a = int(input('digite a primeira nota: \n'))
if a > 10:
    a = int(input('Nota invalida digite novamente: \n'))
b = int(input('digite a segunda nota: \n'))
if b > 10:
    b = int(input('Nota invalida digite novamente: \n'))
c = int(input('digite a terceira nota: \n'))
if c > 10:
    c = int(input('Nota invalida digite novamente: \n'))
d = int(input('digite a quarta nota: \n'))
if d > 10:
    d = int(input('Nota invalida digite novamente: \n'))

media= (a + b + c + d) / 4

if media < 11:
    print('a media é : {}\n'.format(media))
else:
    print('uma ou mais notas não sao validas')

Answer 1

It could create an auxiliary function to keep the user in a loop while there is a successful read of an integer. Here is an example of how this auxiliary function can be implemented.

def lerInteiro():
     while True:
        try:
            a  = int(input('digite a nota: \n'))
            if a >= 0 and a <= 10:
                return a
            raise Exception
        except:
            print("Não foi possível ler o valor digitado como uma nota válida")

then could use the auxiliary function to read the values of the notes in your code, I am exemplifying here the reading of only one value, but can be done in reading all variables (a,b,c,d):

a = lerInteiro()

Explaining the code:

We put the user in a repeat loop while so that until a conversion (to whole) occurs successfully.

Additionally I put a range check of the values accepted for this case we accept only values between 0 and 10.

We use a Try block to ensure that the entered value can be converted to integer value. Otherwise we show an error message directing the user to try to solve the problem.