素因数分解

factor.py

#!/usr/bin/env python3

import math
import sys
def main() -> int:
    if len(sys.argv) != 2:
        print("error")
        return 1
    num:int = int(sys.argv[1])
    primes:list[int]=factor(num)
    print(primes)
    print(str(num) + " = " + str(math.prod(primes)))
    
    return 0

def factor(target:int) -> list[int] :
    current:int = target # 割られる数の残り どんどん素数で割られて最終的に1になるはず
    loop:int =2 # ループ用 最終的に√targetまで増加
    primes:list[int]=[] # 素因数

    while (current != 1 and loop < int(math.sqrt(target)) ): # ⇔ !(current == 1 || loop < √target)
        print(loop)
        if (current%loop == 0 ):
            primes.append(loop)
            current=current/loop
        else:
            loop+=1
    return primes

if __name__ == "__main__":
    sys.exit(main())