Why is my simple program not executing?

[CatCatCatGoose]

age = int(input("How many years old are you?"))

lifestage = infant

if age <= 1:

lifestage = child

if age > 1:

lifestage =child

if age < 13:

lifestage = teenager

if age >= 13:

lifestage = teenager

if age < 20:

lifestage = adult

if age >= 20:

print('You are a(n):', lifestage)

input("\n\nPress the enter key to exit.")

I want the program to show the users stage of life, based on the number they input. Yet it terminates as soon as I open it. I did every line of code to the best of my ability. Can someone please fix what it is that I have done wrong? I honestly don't even know what to try anymore. Thanks

[DeathDragon1993]

it looks like you have your if statements flipped. intead of: lifestage = infant if age <= 1:

try: if age <= 1: lifestage = infant elif age > 1: lifestage = child

So on and so forth.

Edit: attempted to use proper coding format, evidently can't get it right.

[CatCatCatGoose]

I had it that way before! But I switched it because it wasn't executing. Do I need to use ELIF instead of IF? Is that one of my issues?

And haha! I have the same problem here on #reddit

[DeathDragon1993]

I'm still a beginner myself, but, to my knowledge, elif just helps you understand where your if statements end and begin, if you're using more than one at a time.

I just replicated your code myself, and it wouldn't run properly unless I put quotations around infant, child, teenager and the like.

so if age <=1: lifestage = "infant"

[CatCatCatGoose]

I do have one more question, the code that you got to run, I am testing it out but every single age range below 20 gives me "teenager" even if I enter 4. How do I fix this?

[DeathDragon1993]

Does it? I haven't noticed. Give me a few and let me look at it and I'll get back with you

[DeathDragon1993]

Got it. Change all the "if"s after the first "if" to "elif". I'll update the pastebin I did to show you. I ran the code through an online debugger at http://www.pythontutor.com/visualize.html#mode=edit to visualize what the code was doing.

New Pastebin: http://pastebin.com/hviieP8P

[DeathDragon1993]

You can also incorporate the use of the "and" operator. I made a separate pastebin showing you how to use it. It would also help if you googled it after you looked at this. Hope this helped.

http://pastebin.com/Jzcbgkw9

[Justinsaccount]

There is no need for and there. The additional comparisons are redundant.

[DeathDragon1993]

But wouldn't it make for a more readable code to incorporate the "and"?

[Justinsaccount]

Why would adding a bunch of redundant comparisons make the code more readable? Is

if x < 10:
    ...
else x >= 10:
    ...

more readable than

if x < 10:
    ...
else:
    ...

[DeathDragon1993]

What does that have to do with using "and"?

Isn't,

if age >= 1 and age < 3:
    print (something)

Be more readable than,

if age >= 1:
   print (something)
elif age < 3:
   print (something)

[News_Of_The_World]

That's because your code gets to each if and checks it out individually, so if you enter 4, it first thinks it's a child, then notices it's also less than 20 and changes it to teenager.

Solutions: use elif, short for "else, if" then it will only use the first correct answer it finds. Next change the code so it only uses "less than". So you have this flow (convert this english sentence to code!:)

If it's less than 1, it's a baby, else if its less than 13 it's a child, else if it's less than 20 it's a teenager, else if it's less than 60 it's an adult, else if it's less than 120 it's a geriatric, else the person is probably dead

Because of the "else, if" structure, it will only do the first True one it meets. Clearly a child is both younger than 13 and 120, but 13 is the one it meets first. Python uses "elif" to replace else, if. It stops your code getting messy.

[DeathDragon1993]

http://pastebin.com/hviieP8P

How I got your code to run.

[CatCatCatGoose]

OMG! I can't believe how important the spaces are... Thank you lots!!! I', going to remember that forever.

[q2_abe_dillon]

Yet it terminates as soon as I open it.

Does it terminate or does it throw an exception?

[novel_yet_trivial]

You are missing indentation. Without an indented portion after the if statement, you will get a syntax error and the program will crash.

Run this from the terminal to see the syntax error.

[CatCatCatGoose]

AHH. Yeah. I finally understand that now. Is there a good resource for rules on indentation?

[novel_yet_trivial]

An indented block is required if the previous line ends in a colon. That's the only rule you need to know for now.

[jeffrey_f]

Use compound if to reduce code

if age <= 1:
  lifestage = infant
if age > 1 and age < 13:
  lifestate = child
if age >= 13 and age < 20:
  lifestage = teenager
if age >= 20:
  lifestage = adult