Most Profit Assigning Work

Sort by the shared threshold

Create (difficulty, profit) pairs and sort them by difficulty. Sort worker abilities. Sweep workers from weakest to strongest while advancing a job pointer through every job whose difficulty is at most the current ability. Maintain bestProfit, the largest profit among all jobs seen; add it for that worker.

The invariant is that immediately before a worker is scored, the processed jobs are exactly the feasible jobs, so bestProfit is the best legal assignment. Workers are independent, so the same job may be used repeatedly unless the interviewer changes that rule. Sorting costs O(j log j + w log w) and the sweep is O(j + w) time; extra space is O(j) for pairs, or lower if jobs can be reordered in place. Include a worker who cannot do any job, jobs with decreasing profits as difficulty rises, duplicate difficulties, and empty lists. A binary-search-per-worker alternative is valid but usually less direct.