This example demonstrates the Strategy design pattern in C# for dynamically selecting shipping cost algorithms in an e-commerce system. It defines an `IEstrategiaEnvio` interface with two concrete implementations, `EnvioExpress` and `EnvioEstandar`, each providing a distinct cost calculation formula based on package weight and distance. The console application prompts the user for these inputs, lets them choose a shipping type, and then calculates the final cost via a `Pedido` class that holds the selected strategy. The code uses standard .NET APIs like `Console.ReadLine` and `double.Parse` for user interaction, with a compiled output shown in a static screenshot.