Package g1301_1400.s1352_product_of_the_last_k_numbers

Class ProductOfNumbers

java.lang.Object
g1301_1400.s1352_product_of_the_last_k_numbers.ProductOfNumbers
public class ProductOfNumbers extends Object
1352 - Product of the Last K Numbers\. Medium Design an algorithm that accepts a stream of integers and retrieves the product of the last `k` integers of the stream. Implement the `ProductOfNumbers` class: * `ProductOfNumbers()` Initializes the object with an empty stream. * `void add(int num)` Appends the integer `num` to the stream. * `int getProduct(int k)` Returns the product of the last `k` numbers in the current list. You can assume that always the current list has at least `k` numbers. The test cases are generated so that, at any time, the product of any contiguous sequence of numbers will fit into a single 32-bit integer without overflowing. **Example:** **Input** ["ProductOfNumbers","add","add","add","add","add","getProduct","getProduct","getProduct","add","getProduct"] [ [],[3],[0],[2],[5],[4],[2],[3],[4],[8],[2]] **Output:** [null,null,null,null,null,null,20,40,0,null,32] **Explanation:** ProductOfNumbers productOfNumbers = new ProductOfNumbers(); productOfNumbers.add(3); // [3] productOfNumbers.add(0); // [3,0] productOfNumbers.add(2); // [3,0,2] productOfNumbers.add(5); // [3,0,2,5] productOfNumbers.add(4); // [3,0,2,5,4] productOfNumbers.getProduct(2); // return 20. The product of the last 2 numbers is 5 \* 4 = 20 productOfNumbers.getProduct(3); // return 40. The product of the last 3 numbers is 2 \* 5 \* 4 = 40 productOfNumbers.getProduct(4); // return 0. The product of the last 4 numbers is 0 \* 2 \* 5 \* 4 = 0 productOfNumbers.add(8); // [3,0,2,5,4,8] productOfNumbers.getProduct(2); // return 32. The product of the last 2 numbers is 4 \* 8 = 32 **Constraints:** * `0 <= num <= 100` * 1 <= k <= 4 * 104 * At most 4 * 104 calls will be made to `add` and `getProduct`. * The product of the stream at any point in time will fit in a **32-bit** integer.

  • Constructor Details

    • ProductOfNumbers

      public ProductOfNumbers()

  • Method Details

    • add

      public void add(int num)

    • getProduct

      public int getProduct(int k)