2742 - Painting the Walls\.

Hard

You are given two 0-indexed integer arrays, cost and time, of size n representing the costs and the time taken to paint n different walls respectively. There are two painters available:

• A** paid painter** that paints the <code>i^th</code> wall in time[i] units of time and takes cost[i] units of money.

• A** free painter** that paints any wall in 1 unit of time at a cost of 0. But the free painter can only be used if the paid painter is already occupied.

Return the minimum amount of money required to paint the n walls.

Example 1:

Input: cost = 1,2,3,2, time = 1,2,3,2

Output: 3

Explanation: The walls at index 0 and 1 will be painted by the paid painter, and it will take 3 units of time; meanwhile, the free painter will paint the walls at index 2 and 3, free of cost in 2 units of time. Thus, the total cost is 1 + 2 = 3.

Example 2:

Input: cost = 2,3,4,2, time = 1,1,1,1

Output: 4

Explanation: The walls at index 0 and 3 will be painted by the paid painter, and it will take 2 units of time; meanwhile, the free painter will paint the walls at index 1 and 2, free of cost in 2 units of time. Thus, the total cost is 2 + 2 = 4.

Constraints:

• 1 <= cost.length <= 500

• cost.length == time.length

• <code>1 <= costi<= 10⁶</code>

• 1 <= time[i] <= 500