A growing trend of supermarkets selling a cheaper, less nutritious alternative to tinned mackerel is an example of skimpflation, a consumer group has said. Princes - which supplies major supermarkets - has substituted the fish for jack mackerel, an entirely different species also being sold by Lidl. The switch has been spurred by dwindling stocks of Atlantic mackerel after years of overfishing, with its Chilean counterpart more sustainable and a third of the cost. It's a real concern when manufacturers quietly downgrade everyday staples like these as shoppers can end up paying the same price for a product that delivers significantly less nutritional quality, Sue Davies, head of food policy at Which?, said. Jack mackerel contains about half as much omega-3 and around a third as much vitamin B12 as traditional mackerel.

Recent years have seen a significant surge in complex AI systems for competitive programming, capable of performing at admirable levels against human competitors. While steady progress has been made, the highest percentiles still remain out of reach for these methods on standard competition platforms such as Codeforces. Here we instead focus on combinatorial competitive programming, where the target is to find as-good-as-possible solutions to otherwise computationally intractable problems, over specific given inputs. We hypothesise that this scenario offers a unique testbed for human-AI synergy, as human programmers can write a backbone of a heuristic solution, after which AI can be used to optimise the scoring function used by the heuristic. We deploy our approach on previous iterations of Hash Code, a global team programming competition inspired by NP-hard software engineering problems at Google, and we leverage FunSearch to evolve our scoring functions. Our evolved solutions significantly improve the attained scores from their baseline, successfully breaking into the top percentile on all previous Hash Code online qualification rounds, and outperforming the top human teams on several. Our method is also performant on an optimisation problem that featured in a recent held-out AtCoder contest.