Infinite loop over list that adds value to it's own sublist

Question

How can I add a value of a list to its own sublist? Input list:

list = ['apple', 'tesla', 'amazon']

My approach so far:

While True:
 
    list = []

    for comp in list:

            #do some modification

            list.append(comp)

Desired printed output is:

'apple', 'apple','apple', etc.
'tesla', 'tesla','tesla', etc.
'amazon','amazon','amazon', etc.

What do you mean by an "infinite loop" ? What are you trying to accomplish? — Mortz, May 18 '22 at 09:57
Does this answer your question? [Modifying list while iterating](https://stackoverflow.com/questions/1637807/modifying-list-while-iterating) — nfn, May 18 '22 at 09:58
@Mortz I want to have the value e.g. 'apple' to be ended, till a condition is met and a 'break' statement is executed. So apple shall be added over and over again. I need to have the the sub-lists in physically separated lists. not just a print statement at the end of each iteration. — Jones L, May 18 '22 at 09:59

score 0 · Answer 1 · answered May 18 '22 at 10:07

If you change your orignal list to a list of lists it can be done as:

list = [['apple'], ['tesla'], ['amazon']]

while True:
    for i in range(len(list)):
        list[i].append(list[i][0])

The output on each iteration would be something like:

# for iteration 1
['apple', 'apple']
['tesla', 'tesla']
['amazon', 'amazon']

# for iteration 2
['apple', 'apple', 'apple']
['tesla', 'tesla', 'tesla']
['amazon', 'amazon', 'amazon']

score 0 · Answer 2 · answered May 18 '22 at 10:17

0

list = ['apple', 'tesla', 'amazon']
for idx, item in enumerate(list):
    text = (list[idx]+",")*len(list)
    print(text[:-1])

apple,apple,apple
tesla,tesla,tesla
amazon,amazon,amazon

answered May 18 '22 at 10:17

uozcan12

404
1
5
13

score 0 · Answer 3 · answered May 18 '22 at 10:27

I can think of a couple of ways - I am using the length of each item in the list to define a condition here as you did not specify the condition you are using to move on to the next item -

Option 1 - using a `for` with a `while` loop

l = ['apple', 'tesla', 'amazon'] 
x = 0
for comp in l:
    while x < len(comp):
        print(comp)
        x += 1
    x = 0

Option 2 - using `while` with a `iter`

l = ['apple', 'tesla', 'amazon'] 
x = 0
it = iter(l)
while True:
    try:   
        item = next(it)
        while x < len(item):
            print(item)
            x += 1
        x = 0
    except StopIteration:
        break

In both cases - the output is

apple
apple
apple
apple
apple
tesla
tesla
tesla
tesla
tesla
amazon
amazon
amazon
amazon
amazon
amazon

Infinite loop over list that adds value to it's own sublist

3 Answers3

Option 1 - using a for with a while loop

Option 2 - using while with a iter

Option 1 - using a `for` with a `while` loop

Option 2 - using `while` with a `iter`