Diet Problem (DP) involves finding the most cost-effective diet that meets all nutritional requirements. Imagine you have a list of foods, each with its own nutritional content and cost. Your goal is to choose a combination of these foods that provides all the necessary nutrients (like vitamins, proteins, carbohydrates, etc.) for the least possible cost. You set up equations for each nutrient, ensuring your diet doesn't fall short or exceed what's needed. Then, you use linear programming to minimize the total cost while satisfying these nutritional constraints. It's like solving a puzzle where you balance your health needs against your budget, finding the best possible dietary plan.