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Prime factorization

A program that breaks a number into its prime factors and notes the time it took.

Goal

Turn a mathematical method into loops myself, without a ready-made library.

Implementation

Three versions with my own logic: numbers still to be split go into one list, the primes found into a second one.
Nested loops check the divisors from both ends at once.
Start and end time show how long the factorization took.

Code

The factorization in three nested loops

primfaktor_v3.py

while True:
    if sum(control_numbers) == 0:
        end = datetime.now()
        endtime = end.strftime('%H:%M:%S')
        if len(prime_number) == 1:
            print(line)
            print(f"|Startzeit: {starttime} | Endzeit: {endtime}]")
            print(f"Die Zahl {number:.0f} ist eine Primzahl")
            print(line)
            break
        else:
            print(line)
            print(f"[Startzeit: {starttime} | Endzeit: {endtime}]")
            print(f"Deine zerlegte Zahl: {number:.0f}")
            print(" x ".join(f"{zahl:.0f}" for zahl in prime_number))
            print(line)
            break
    else:
        while True:
            if control_numbers[0] <= 2:
                prime_number.append(control_numbers[0])
                control_numbers.pop(0)
                break

            elif control != control_numbers[0] or counter > counter2:
                control = 0
                control += control_numbers[0]
                counter = 2
                counter2 = 0
                counter2 = counter2 + control_numbers[0] - 1
            else:
                while True:
                    if control_numbers[0] <= 2 or counter > counter2:
                        prime_number.append(control_numbers[0])
                        control_numbers.pop(0)
                        break
                    elif control_numbers[0] % counter != 0 and control_numbers[0] % counter2 != 0:
                        counter += 1
                        counter2 -= 1
                        print(f"{control_numbers} {counter} {counter2}")
                    else:
                        control_numbers.append(counter)
                        control_numbers.append(control_numbers[0] / counter)
                        control_numbers.pop(0)
                        break
                break

Numbers move between two lists until only primes are left.

What I learned

Thinking a process through on paper first, and how quickly nested loops get hard to follow.