Leetcode 1829 Solution

class Solution:
    def maximumUnits(self, boxTypes: List[List[int]], truckSize: int) -> int:
        boxTypes = sorted(boxTypes, key = lambda x: x[1], reverse=True)

        i = 0
        ans = 0
        while truckSize > 0 and i < len(boxTypes):
            box_num, unit_num = boxTypes[i]

            target_num = min(truckSize, box_num)

            truckSize -= target_num
            ans += target_num * unit_num

            i += 1

        return ans