🔒 Nested for loop

[final vine]

@silk monolith

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[silk monolith]

@naive ore

[flint garnet]

whats your goal?

[normal pilot]

Ok I see what you're trying to do

[normal pilot]

Make a tree of stars

[flint garnet]

ooh

like visually?

[normal pilot]

see their output comments

[silk monolith]

oh ye

this is my goal

im stuck

at loops

[naive ore]

Do you have any code yet?

[silk monolith]

for like 3 months now

[silk monolith]

ye let me show u what i tried

[silk monolith]

actually i dont have any for this problem it confused me alot

like i didnt even know where to start

started coding in like january

and i got stuck at loops

for 3 months

[naive ore]

i see you are frustrated. You don't need to tell us you are stuck at loops again.

what is the first loop you will need for this? it prints 5 lines of output, right?

[silk monolith]

ye

i guess so

so set height = 5

for i in range(height):

[naive ore]

ok, good start.

[silk monolith]

and now im stuck

idk what to do from here

[naive ore]

for the first line, how many spaces do you need to print, and how many stars?

[silk monolith]

well it is 4 spaces

[naive ore]

yes, for the first line, and how many spaces for the second line?

[silk monolith]

3

so we are going down in a step of -1

so second for loop

for j in range(height-1)

[naive ore]

make a program with those two loops, and print the values of i and j, and see if they are what you want.

[naive ore]

but first, pick better names. what does i represent, and what does j?

[naive ore]

you did very well to use end="", was that your own idea?

[silk monolith]

ye it's in a text book of mine to use it

i know when to use it kinda

but i dont understand what it does

it just makes it so output isnt just

"********************"

[naive ore]

it means, print stuff, and don't end the line yet.

Notice that all of your lines look the same, why is that?

[silk monolith]

well i suppose it's meant to be like that, no?

[silk monolith]

it's printing this

im missing something like height-1

[naive ore]

"it's meant to be like that"? It's your program you decide what it should be like.

[flint garnet]

end() basically tells the code what comes after you text

[silk monolith]

i guess im trying to make it readable

and not clutter it

but my logic is hindered by doing so

[naive ore]

sorry, when I said your lines are all the same I meant the lines of output

[flint garnet]

you could do it so it ends with ', ' so when you print values, it goes "a, b, c, d..."

[naive ore]

(i have to be away, others will help)

[silk monolith]

oh

[flint garnet]

ill help dw

[silk monolith]

well theres nothing distinct in a line of code i have written so far

[flint garnet]

so

@silk monolith

[flint garnet]

what are you tying to do again?

print a tree right?

[flint garnet]

this?

[silk monolith]

im tryna outpyt this

[flint garnet]

yea

so

first line

how much spaces does it have?

[silk monolith]

6-1

[flint garnet]

second?

[silk monolith]

wait no

it has 4

2nd line has 3

3rd line has 2

[flint garnet]

yeah

[silk monolith]

so there is a pttern of -1

[flint garnet]

yeah

-1 space, +1 *

the last row has 5 *

and 0 spaces

and the first one has 4 apces and 1*

each loop, you want one less space and one more star

[silk monolith]

ok im confused i just messed around with my code and it actually worked

i have no idea

how i did it

why i did it

[flint garnet]

wait

[silk monolith]

i just did trial and error

[normal pilot]

OK A solution has been found

[silk monolith]

this has taken me an entire day to solve

[flint garnet]

oof

[ruby forge]

Do you understand why the outer loop (for i)?

[silk monolith]

and i still dont understand how

[silk monolith]

i have no idea at all man

i just did trial and error

[ruby forge]

Ok.

[silk monolith]

for a whole day

sounds like im a bad coder icl

[flint garnet]

nu uh

[ruby forge]

Think: how many rows do you want to draw? That is the height.

[flint garnet]

everyone can code

[silk monolith]

5

[flint garnet]

you just need to learn

[silk monolith]

there's someone in my grade (grade 10) whos a professional coder and even made his own programming language

[normal pilot]

Ok well let me try helping:
rename i to row_number
rename j to num_spaces
rename k to num_stars

It may help

[silk monolith]

he's just turned 16 btw

[ruby forge]

A for loop iterates over something. In Python range(n) gets you an iterable on n items (0,1,2,3,4) in your case.

[flint garnet]

damn

nice

[silk monolith]

mhm i see

[normal pilot]

dubs

[silk monolith]

he's insane at coding and using neovim

pure sweat

compiles

[flint garnet]

yea good tip

[silk monolith]

his own language

[ruby forge]

Tehn inside the loop you just do whatever is needed for that single line.

[flint garnet]

you should get used to naming your varibles names instead of letters

so you understand better

[silk monolith]

oh

i just see youtube

but its terribly explained

[flint garnet]

yeah

[silk monolith]

it just explain basic stuff

not logic

NO video explains logic

they're all useless

[normal pilot]

I personally recommend W3 Schools python course

[silk monolith]

im so confused

[ruby forge]

Here you're taking HW's suggestion of the pattern - more spaces according to the current height (i) and fewer asterisks.

[normal pilot]

Its free

[flint garnet]

they have a course?

[flint garnet]

a free one too?

[normal pilot]

https://www.w3schools.com/python/

[silk monolith]

i've used it

it explains basic stuff

i wanna become a coder

who can do all kidns of stuff in python

[flint garnet]

huh

[normal pilot]

Basics is how it starts up

[flint garnet]

i always thought it was explaining everything in python

[silk monolith]

well i got the basics in the bag i think

[flint garnet]

and other stuff

[ruby forge]

One approach might be: what would you tell someone else about doing this, on paper with a pen, if you were instructing them. Not for loops or anything, stuff like "write down lines of space and asterisks, this many, how many etc". In English. Then translate.

[flint garnet]

not an actual course when you learn step by step

[normal pilot]

Welcome to Pseudocode

[silk monolith]

yes this is a majour issue with the exam board in doing at GCSE

it does pseudocode

but our teacher

[normal pilot]

they try... a lil

[silk monolith]

is horrid

[ruby forge]

Aye, but a good way from going from your mental idea of what to do to actionable things.

[silk monolith]

also in our exam we have easy questions

i can do them

[normal pilot]

I feel ya, i had 3 teachers in one year

[silk monolith]

i get like 6/7 in the problems

[normal pilot]

none of them knew python

[silk monolith]

and always lose a mark due to logic error

[silk monolith]

nah he knows python

[flint garnet]

yeah, its like learning a new language, to speak, you need to know the translations, then you get used to knowing what the new words mean

[silk monolith]

can't explain it that well

[ruby forge]

You explained it to HW.

[flint garnet]

so just use something you're familiar with to represent what you're trying to do

[silk monolith]

alright can you give me an example that i code now

[flint garnet]

like ms paint

[silk monolith]

i am gonna use this approach

[silk monolith]

ill use pen and paper

[flint garnet]

sure

pick whatever explains it better

[silk monolith]

can u give me an example

not example

like challenge

like rn i did the star one

[flint garnet]

ah

[ruby forge]

Print the even numbers up to 20.

[silk monolith]

can you give me another

[silk monolith]

alright

[flint garnet]

yea good into to loops

[ruby forge]

Tell me what you would do, if you were doing it on paper.

[flint garnet]

i already know a mistake he might make

well not a mistake, just something he can improve

[ruby forge]

Let the OP have a go.

[flint garnet]

yea

[ruby forge]

We're not after "best", we're after "working".

[normal pilot]

As always

[silk monolith]

it worked

[normal pilot]

That is one solution

[ruby forge]

Yay.

[flint garnet]

smart

now use a while loop

[ruby forge]

So, you seems ok with that one.

[flint garnet]

if you know what it is

[silk monolith]

alright ill use while loop

[silk monolith]

yikes i got stuck with infinite while loop

[flint garnet]

lets say it was from 1 to 100

[silk monolith]

while num <= 20*

[ruby forge]

That's because you don't change num in the loop. Since it never changes, you never reach your bound of 20.

[flint garnet]

would you write each number 1 to 100?

[silk monolith]

no

it would be too slow

[ruby forge]

You also want to set it to 0 (or 1) before the loop. It will have the 20 from the for loop earlier otherwise.

[silk monolith]

and inefficient

[flint garnet]

what if you just do the same as the for loop does?

just make a varible and make it so that it increases every loop

i mean ill give you a hint, you can do this with like 4 lines of code

without the if

[silk monolith]

aight

[silk monolith]

when do i use return

[flint garnet]

return is more like a function thing

[flint garnet]

print works just fine

you want the answer?

[silk monolith]

ah crap

im stuck

this is not working properly

[flint garnet]

wdym?

[ruby forge]

Again: you're not changing i. So the condition of the while never changes.

[flint garnet]

oh right

[silk monolith]

i dont get what u mean

"changing i"

?

[flint garnet]

unlike for loops, while doesnt increase the number

[ruby forge]

A for loop takes each item from the iterable (above, range(1,21)).
For a while loop you provide that mechanism.

[flint garnet]

set i to the next number

set i as i+1

[ruby forge]

i = i + 1

[flint garnet]

or

i+=1

[ruby forge]

You also want to set i = 1 above the loop.

Because you've got i=20 from the for loop preceeding it, and you need to start over.

[flint garnet]

whats if you just set the loop as while i <= 20:

[ruby forge]

Good, setting i=1

[flint garnet]

so while i is less than or equal to 20

[silk monolith]

still it doesn't work

[ruby forge]

Now add code to the while loop to add 1 to i each time.

[silk monolith]

or i could just

[flint garnet]

hm?

[silk monolith]

it worked

[ruby forge]

Yay.

[flint garnet]

yup

nice

[silk monolith]

why do i need to set i = 1

[ruby forge]

Do you understand why it's better?

[silk monolith]

at start

[silk monolith]

the while loop version?

ye less code

more efficient?

[ruby forge]

Because earlier you had that for-loop counting i from 1 through 20. So i was 20 after that.

i needs to start somewhere anyway. Setting it to 1 is that somewhere.

[flint garnet]

yknow you can remove the if

[ruby forge]

Essentially the same.

[flint garnet]

each even number is +2 the before one

[silk monolith]

im gonna be honest

for this while loop one

i used gpt

for help

i thought it would guide me

[flint garnet]

its okay

[silk monolith]

it just gives the answer

[flint garnet]

i use it all the time

[silk monolith]

its so tempting

i feel like a good coder has no need to use gpt

[ruby forge]

The problem there is twofold: 1: GPT just makes stuff up sometimes and 2: you haven't figured out the solution yourself.

So: what's different about the new, working code.

[flint garnet]

just tell us what you're trying to make with words and then translate it into python

[silk monolith]

i +=1

[ruby forge]

Right. Why is that important?

[silk monolith]

i have no clue

[ruby forge]

Ok. What does it do?

[silk monolith]

so i counts up to 20

but why is it at the end

[flint garnet]

wait lemme explain

[silk monolith]

shouldnt that be a logic error

[ruby forge]

Right. If you don't count, i stays at 1 and the while loop never finishes.

It is a logic error, but Python doesn't know what you're trying to do. So it can't tell you what's wrong.

[silk monolith]

if i did this

it wouldnt work at all

[ruby forge]

Yes.

[silk monolith]

now if i shift i+=1 at the end

it works?

confusing logic

[flint garnet]

ooh

so basically

when theres an if,loop,function, yadda yadda

[ruby forge]

The problem isn't putting i+=1 at the end (though that is the natural place for it, just before the next loop). The probem is that being inside the if it doesn't happen if the if is false.

[silk monolith]

oh

[ruby forge]

So you want the print() inside the if, because that should/should-not happen dpeneidng on the value of i.

But the i+=1 should always happen. So it goes outside the if.

[silk monolith]

i have a question

how did u learn this logic

not logic

chain of reasoning

to solve a problem

i am confused as hell

[ruby forge]

I already thought this way when I learnt to programme.

[silk monolith]

my thinking process is fixed

[ruby forge]

Basicly: you're telling Python exaclty what needs to be done. Leave nothing out.

[silk monolith]

alright can you give me another problem

that i can do

[flint garnet]

uhh

[silk monolith]

this one i kinda get now

[flint garnet]

do you know random?

[silk monolith]

yes

import random

[flint garnet]

https://www.w3schools.com/python/ref_random_randint.asp

use randit

[silk monolith]

i've used randit

[flint garnet]

and make a little game

[silk monolith]

trying to make number guessing game

[ruby forge]

TO me there are 2 basdic sides to this:

• take your problem, express it in english as to a person.
• Python needs to be told everything it needs to do. Translate your english into python, getting more detailed until everything has been said.

[silk monolith]

alright

is there any job

computer science related

high paying

without coding

LMAO

sql is way easier than any coding language

im learnign that steadily as well

[flint garnet]

where the program picks a random number, and you try to guess it, it tells you if its higher or lower, the game ends when you correctly guess the random number

[ruby forge]

Oh wait until you write a complicated bit of SQL.

[silk monolith]

oh...

[ruby forge]

SQL's hard enough that we (programmers) often use ORMs (object relation managers) just to avoid writing it 🙂

[flint garnet]

@silk monolith

[silk monolith]

ye?

[flint garnet]

make a number guessing game

BUT

first

tell us what your plan is

how will you make it

[silk monolith]

alright im writing it in # vscode first

then ill screenshot it here

[flint garnet]

nope

tell us

[ruby forge]

Describe it in english to us first.

[flint garnet]

explain what you're gonna do

@silk monolith

[silk monolith]

one question

when should i do

when should i use

a chain of if statemnts

opposed to a chain of if then elif elif elif

[flint garnet]

tell us what your plan is

then write the syntax

[silk monolith]

@flint garnet

[flint garnet]

hm

a long range would be better

like 1-100

also tell the player if their number is higher or lower

[silk monolith]

i've almost done it

btw

how do i use \n

new line

omg i did it

i think

@flint garnet

@ruby forge

[flint garnet]

chatgpt?

[silk monolith]

no i swear on allah

i didnt use gpt

[ruby forge]

Good.

But I suspect you tested it with a correct guess?

[silk monolith]

i did make some errors initially

but then

i tested it

and fixed it

[ruby forge]

I'm saying that because you pick a different random number on every pass through the loop, making the guess something of a moving target.

[silk monolith]

like i didnt have while loop initially

[silk monolith]

wdym

[ruby forge]

To see what's going on, add:

print("randomGuess", randomGuess)

after the randomGuess = line.

[silk monolith]

OHH

i see

[ruby forge]

Just do it once, before the loop.

[silk monolith]

i intergrated it within the loop

can you give me a problem where i have to use some looping

together

btw

when would you typically use for loops

iterating through lists

?

and what else

@naive ore @ruby forge @flint garnet thanks for the advice you're giving me btw helped me solve problems a bit better i guess

[flint garnet]

nice

[silk monolith]

can you give me a problem where i have to use some looping
together

[flint garnet]

i have an idea

tho idk if youll be able to do it

[silk monolith]

just tell me

[flint garnet]

math quiz

basically

[silk monolith]

what is 12 * 1

12 x 1

[flint garnet]

kinda

so

[naive ore]

another idea: print a multiplication table

[flint garnet]

hm

[silk monolith]

ah

[flint garnet]

yeah good idea

[silk monolith]

like?

[naive ore]

(as a table with columns and rows if you get fancy)

[silk monolith]

like this?

[flint garnet]

yup

[naive ore]

yes,but in your terminal

[silk monolith]

ah i see

[silk monolith]

btw

there's a guy in my grade

who's learnt like 8 languages

made his own language

and compiler for it

and he codes for "fun"

[naive ore]

pro tip: never compare yourself to others

[silk monolith]

academic scholar as well

[silk monolith]

mhm

i kinda do that to a lot tho

like this year i had some pretty good grades

even got an A in comp sci

[naive ore]

that's great. But you shouldn't compare yourself to others.

[silk monolith]

you sure?

[naive ore]

i am sure. what's the point.

[silk monolith]

god this question is hard

im stuck

[flint garnet]

okay

explain what you're thinking

[silk monolith]

well you have rows

and then columns

lets set both to 12

so we have 2 nested for loops

[naive ore]

yes

[flint garnet]

have you used loops in loops?

[silk monolith]

why does this give me an error

[flint garnet]

cus

range doesnt supposrt end

[silk monolith]

oh

[flint garnet]

end is for strings

[silk monolith]

ok i know now

[flint garnet]

range(start, stop, step)

[silk monolith]

im thinking this so far

but its not giving me the cofrrect thing

[flint garnet]

if theres only one value then its stop by deafault

copy the code here

[final vine]

Hey @silk monolith!

Please edit your message to use a code block

```py
print('Hello, world!')
```

This will result in the following:

print('Hello, world!')```

[flint garnet]

ah

[silk monolith]

for column in range(13):
    for row in range(13):
        print(column, end = " ")
        print(row)

[flint garnet]

its correct

[silk monolith]

it's not

[flint garnet]

the formatting isnt tho

[flint garnet]

yeah

yknow why?

[silk monolith]

its due to my for loop

it iterates in a wrong way

[flint garnet]

what does end="" do?

[silk monolith]

not wrong by python

[silk monolith]

sends thing on new line

?

[flint garnet]

nope

the name tells you

[silk monolith]

ends it

on that line

[flint garnet]

with what?

[silk monolith]

a "

""

[flint garnet]

yup

anything you put in thoes, itll end the string with it

[silk monolith]

, end = " "

so remove this?

[flint garnet]

what would

print("test", end=", ")
print("try")

do?

what would it print?

[silk monolith]

test, try

[silk monolith]

test, try

[flint garnet]

yup

now split that into what prints what

[silk monolith]

well it's same as

print("test,try")

columb, row

12, 1

12, 2

12, 3

thats what i was getting

what do i do here

[flint garnet]

answer this

[silk monolith]

wdym

by this question

[flint garnet]

you have "test, try"

[silk monolith]

ye

[flint garnet]

one part is the first print, another part is the end to the first print, and the last part if from the second print

so where are the parts split

?

[silk monolith]

i see what im doing wrong

im not actually doing any multiplication

``py

for i in range(1, 7):
    for j in range(1, 7):
        print(i * j, end=" ")
    print()

[final vine]

Hey @silk monolith!

Please edit your message to use a code block

Make sure you put your code on a new line following py. There must not be any spaces after py.

Here is an example of how it should look:
```py
print('Hello, world!')
```

This will result in the following:

print('Hello, world!')```

[final vine]

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