# https://leetcode.com/problems/product-of-the-last-k-numbers

from typing import List

class ProductOfNumbers:
    prefix: List[int]

    def __init__(self):
        self.prefix = []

    def add(self, num: int) -> None:
        if num == 0:
            self.prefix = []
        elif len(self.prefix) >= 1:
            self.prefix.append(self.prefix[-1] * num)
        else:
            self.prefix.append(num)

    def getProduct(self, k: int) -> int:
        if k > len(self.prefix):
            return 0
        if k == len(self.prefix):
            return self.prefix[-1]
        return self.prefix[-1] // self.prefix[-k -1]