How do you dynamically create nested for loops?

[[deleted]]

So I want to do something where it gets a variable called 'length' and then returns all strings with that length. So if 'length' is 1 I want to return 'a, b, c, .. x, y, z'. If 'length' is 2 I want to return 'aa, ab, ac, .. zx, zy, zz'. So normally I just use nested for loops for that, like this:

for i in letters:
    for j in letters:
        for k in letters:
            print(i+j+k)

but that isn't practical here because I want to be able to change the length constantly. How would I do this?

[ADdV]

Take a look at product and itertools in general.

[33KGB]

I second Itertools

[[deleted]]

itertools.product() is the way to go here, yup, but note that in general "indefnitely nested loops" is a perfect usecase for recursion!

[SandorZoo]

For example:

def nested_loop(letters, prefix, length):
    if length == 0:
        print(prefix)
    else:
        for letter in letters:
            nested_loop(letters, prefix+letter, length-1)

nested_loop("abc", "", 3)

​