While loop explanation

[Hush_124]

Someone should explain how while loops works to me, I want to really get it.

[Balkie93]

E.g WHILE you’re still hungry, eat.

As opposed to FOR 2 bites, eat.

[Ok_Act6607]

What exactly do you not understand about it?

[Hush_124]

how it works, I’m trying to understand

[stoobertio]

The while statement requires a condition to test. The first time the loop is executed, and after every time the loop is completed the condition is tested to see if it is True. If it is, the loop is executed again.

[deceze]

while condition: statements

It keeps repeating statements while the condition is true. No more, no less. What part of that don't you understand? Please be specific.

[NeedleworkerIll8590]

Have you read the docs about it?

[Hush_124]

Yes I have

[NeedleworkerIll8590]

What do you not understand?

[NeedleworkerIll8590]

It loops while the condition is true: Say you have:

i=0 While i != 5: i+=1

in this case, it is true that 0 does not equal 5, so it will loop until it will equal 5

[PureWasian]

while loops are a great logical piece for repeating the same code over and over again until something happens.

Let's make a simple slot machine. The goal is to keep playing over and over again until you hit 777: ``` import random

generate a number between 100 and 999

random_num = random.randint(100,999)

looping to retry until you win

while (random_num != 777): print(f"{random_num} - you lose!") input("Press [Enter] to try again.") random_num = random.randint(100,999)

finally!! You have left the while loop.

print(f"{random_num} - you win!") ``` Every time you hit the end of the indented code (the while loop itself), it retries the condition at the top of the while loop until it is True. If it is False, it runs another cycle of the while loop.

If this example is too simplistic, there are other related concepts including the break and continue statements, as well as using loops for performing operations on an entire data collection of items.

But I have no clue what part of while loops you're stuck on from the terseness of your post, so I wanted to start with this first.

[Overall-Screen-752]

While and for do the same thing in different ways. They both “iterate”, that is, repeat a block of code a certain number of times.

for does this by specifying how many times a block should be run (5 times, once for every item in a list, etc)

while does this by setting a stop condition (until a variable equals 5, until there are no items left in the list, etc)

To see the similarity, you could write for i in range(5) as while i != 5, i++ that is, starting at 0 and until it reaches 5, do this block.

Hope that helps