Python 变量理解

Question

I was writing this code and I can't seem to get it to work correctly. There's no Syntax errors so I'm clear on that. It just is not giving me the correct output I want.

Here's the code:

This is the out put I get when x = 5: Big! Done!

This is the output I get when x = 1 Small! Done!

This is what I get when x = anything other than 1 or 5 Done!

What I want it to do is when x = anything between 1-5 to output Small? then Done! Or if it is between 5-infinity to output Big! then Done! but if the number is not 1 or 5 it just outputs Done! What changes should I do to my code?

Answer 1

x = 5
if x in range(6):
    print('Small')
elif x >=6 :
    print('Big')
print('Done')

Try this. The range function checks if the number is in between 0 and 6 ie 0 to 5. Anything lesser than 0 will be ignored

The problem with your code is that you're just checking two conditions if x== 5 and if x == 1 . The print statements will be executed only if this condition is satisfied.

Cheers

Answer 2

As pointed by a user in the previous answer, what you need to implement is an if-else ladder and use logical operator for the case when your output is specifically either 1 OR 5

x=6 # You can replace this by a user defined input using input()
if x==5 or x==1:
    print("Done!")
elif x<5:
    print("Small!")
    print("Done!")
elif x>5:
    print("Big!")
    print("Done!")
else:
    print("Enter a valid number!")

I checked with various test cases like 1, 5, numbers between 1 and 5 and numbers greater than 5 and all seem to work fine.

Here's a sample output

Answer 3

You can create a if-else ladder to achieve this

def determine_size(inp):
    if inp == 1 or inp == 5:
       print("Done")
    elif 0 <= inp < 5:
       print("Small")
       print("Done")
    elif inp > 6:
       print("Big")
       print("Done")
    else:
       print("Negative Input")

>>> determine_size(0)
Small
Done
>>> determine_size(100)
Big
Done
>>> determine_size(60)
Big
Done
>>> 
>>> determine_size(3)
Small
Done
>>> determine_size(4)
Small
Done

You can also play around with the if-else statements per your objectives

Answer 4

x = 40

# at first check if x is greater than 1 and less than 5.
# Only then it is between 1 and 5.
if x >=1 and x<=5:
    print('Small!')
# Now chek if x is greater than 5
elif x>5:
    print('Big!')
print('Done!')

Answer 5

if you meant the above mentioned scenario mentioned in comment

    try:
      x=int(input("enter a number: "))
      if x >=0 or x<=5:
        print("Small")
        print("Done")
      elif x>=6:
        print("big")
        print("Done")
    except ValueError:
        print("Done")

here the block of code is written in try block, why i have written in try block if someone enter something which is not number then program will not crash and raise a exception .

if you are not familiar with elif syntax, we can have simple construction like this:-

try:
  x=int(input("enter a number: "))
  if x >=0 and x<=5:
    print("Small")
    print("Done")
  else:
    print("big")
    print("Done")
except ValueError:
  print("Done")

Here all I have done is to change the logical operator from or to and .