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All right, now let's look at while.py.

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There are only three
problems in this one but

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they might prove more difficult
than the ones in for.py.

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While loops,

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if you don't remember, will execute until
their condition evaluates as false.

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Because of this,
they're known as indefinite loops,

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because they can run
an indefinite number of times.

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For loops on the other hand,
will only run a certain number of times.

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I don't think it's even possible to
make infinite for loops in Python.

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You can use the continue keyword
to skip an iteration of the loop.

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Or you can use the break keyword
to completely stop the loop.

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Both of those keywords work on for loops
too, but they're used there less often.

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Let's take a look at the problems.

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The first problem, warm the oven,
needs you to add 25 degrees to

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the current oven temperature
until it's at 350 degrees.

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On each iteration,
print out the current temperature.

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When the loop is done,
print out The oven is ready!

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You can use the while loop's
else class here if you want.

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For the second problem, you'll need
to finish the function that I started.

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Yeah, I'm gonna call that started.

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Anyway, create an infinite while loop.

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Since while loops run until
their condition is false,

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what value could you use to
make the condition never false?

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While the loop is running,
ask the user for a number and

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add that number to the numbers list.

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If they give you a q, a string q,
instead though, end the loop.

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When the loop ends, print out all of
the numbers, the sum of the numbers, and

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the average of all of the numbers.

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This solution doesn't absolutely
require you to use break, but

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you'll probably find it
easier to solve that way.

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Finally, the third problem.

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You might have come across the common
programming problem known as fizzbuzz,

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where you have to loop through all
of the numbers from say, one to 100.

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And if the number is divisible by 3 or
5 or 7 or some combination of them or

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some other number, then you print
out fizz, buzz, or fizzbuzz.

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Now I don't want you to do exactly that,
but it's something similar.

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Write a while loop that checks
the value of the current variable.

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This one right here called current.

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If it's 101, you should end the loop.

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On each iteration,
increment the number by 1.

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If the new number is divisible by 3, 5,

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or both, print it out,
otherwise, skip the number.

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All right,
see how you do on these challenges.

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And I'll be back with
the solutions in a minute.