Python-输出不符合预期

Question

My code is as follows:

prompt = '\nPlease tell us your age'
prompt += "\n(Enter 'quit' when you are finished)"

while True:
    age = input(prompt)

    if age == 'quit':
        break
    elif int(age) < 3:

        print ('Your admission is free')
    elif int(age) > 3 < 12:
        print ('Your admission charge is $10')
    else:

        print ('Your admission charge is $15')

    break

Probably a simple answer, but when age entered greater than 12, returns 'Your admission charge is $10' when 'Your admission charge is $15' is expected - Why ?

Answer 1

When you have several condition after your elif statement, the syntax is a bit different :

while True:
   age = input(prompt)
   if age == 'quit':
       break
   elif int(age) < 3:
       print ('Your admission is free')

   elif (int(age) > 3) and (int(age) < 12):
   # Annother possibility :
   #elif 3 < int(age) < 6 : 
       print ('Your admission charge is $10')
   else:
       print ('Your admission charge is $15')

   break

Answer 2

Its because its goint to else condition for example i put 13 , first condition is incorrect going to second, 13 < 3 false , going to third, 13 > 3 here true < 12 here false, the condition is false , now going to else and make the stuff you want on this else in your case the print .

Good example of this situation is use of assert :

assert 13 > 3 and 13 < 12

Answer 3

Probably you have to use AND operator.

elif int(age) > 3 and int(age) < 12:
...

I also recommend casting the input right after you read it - you don't have to write int(age) every time :)

age = int(input(prompt))

Answer 4

Try 3 < age < 12

Your int(age) > 3 < 12 is interpreted as int(age) > 3 && 3 < 12 which is true for all ages over 3