DoorDash Frontend Engineer Coding Questions

DoorDash wants to create bundled promotions that maximize customer engagement while ensuring profit margins. Given an array of integers products representing the price of each product and an integer target, find all combinations of products that sum up to exactly target.Function Signature:
python
combinationSum(products: List[int], target: int) -> List[List[int]]
Example 1:
Input: products = [2, 3, 6, 7], target = 7
Output: [[7], [2, 2, 3]]
Explanation: The combinations that yield 7 are the combinations of products 7 and the numbers 2 and 3 in different quantities.Constraints:
- 1 <= products.length <= 30
- 2 <= products[i] <= 40
- 1 <= target <= 500

DoorDash needs to optimize the delivery routes for drivers by calculating the maximum distance they can cover within a given time frame.
Given an array orders where each entry represents the distance of an order from the restaurant and an integer Time which represents the maximum time available, calculate the maximum total distance of orders that can be completed within that time. The distance for each order is defined as distance[i] = time[i] * speed[i] where speed can be considered constant.Function Signature:
python
maxDeliveryDistance(orders: List[int], Time: int) -> int
Example 1:
Input: orders = [1, 2, 3, 4, 5], Time = 7
Output: 12
Explanation: The driver can complete orders 3, 4, and 5 within the time limit, accounting for the maximum distance covered.Constraints:
- 1 <= orders.length <= 1000
- 1 <= orders[i] <= 100
- 1 <= Time <= 1000