Google | Product of the Last K Numbers
Sithis
14140
GooglePhone ScreeningOnsiteInterview

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

Design a data structure to calculate the moving product of all elements in a sliding window of size k.

class SlidingWindow {

    public SlidingWindow(int k) {
    }
    
    public void add(int val) {
    }

	public int getProduct() {
	}
}

All methods should work in O(1) time.

Example:

SlidingWindow window = new SlidingWindow(3);
window.add(1); // [1]
window.add(2); // [1, 2]
window.getProduct(); // 2
window.add(3); // [1, 2, 3]
window.getProduct(); // 6
window.add(4); // [2, 3, 4]
window.getProduct(); // 24

Follow-up:
What if k is a method argument instead of constructor?

public int getProduct(int k) {
}

You can assume that a product will fit into a single 32-bit integer without overflowing.

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