Make a sequence of letter combinations start with a specific letter

Question

from string import ascii_uppercase 
import itertools 
import time

for seq in itertools.product(ascii_uppercase,repeat=3):
    sseq = ''.join(seq)
    for z in range(11111, 100000):
            passcode = ('%s%05d' % (sseq, z))
            print(passcode)
            time.sleep(0.5)

The initial exit is:

AAA11111
AAA11112
...

How can I change that and make him start from:

FFF11111
FFF11112

Answer 1

To start from the "F", just... put the "F" at the beginning. But then it was not clear what you want...

---

You want it to start from "F" and then go to "Z", excluding all combinations that have the letters from "A" to "E"?

In that case, just use itertools.product(ascii_uppercase[5:], repeat=3) <-- the Slice [5:] take only from "F" onwards (ignoring the letters of "A" and "E"). With this, combinations such as "FAA" and "FEB" will be excluded.

---

Or you want it to start from the "F", but also include all letters?

In this case, simply rearrange the letters by placing the "F" at the beginning:

letras = 'F' + ascii_uppercase[:5] + ascii_uppercase[6:]
for seq in itertools.product(letras, repeat=3):
    etc...

The Slice [:5] take the letters from "A" to "E", and [6:] takes everything from the "G" onwards (up to the "Z"). So, letras will be FABCDEGHIJKLMNOPQRSTUVWXYZ: you will have all letters (and therefore all possible combinations), but now the first ones will be "FF11111", "FF11112", etc.

Answer 2

A solution:

from string import ascii_uppercase as au
from itertools import product
import time

bl = "FFF"  # begin_letters
bn = 11111  # begin number

c = [''.join(i) for i in product(au, repeat=len(bl))]
for s in c[c.index(bl):]: 
    while bn < 100000:
        passcode = ('%s%05d' % (s, bn))
        print(passcode)
        time.sleep(0.5)
        bn += 1
    bn = 0