Round #574

Calculate the percentage of total sales each product represents.

```csharp using System; using System.Data; class Program { static void Main() { // Create a DataTable DataTable dt = new DataTable(); dt.Columns.Add("Product", typeof(string)); dt.Columns.Add("Sales", typeof(int)); dt.Rows.Add("Product A", 1000); dt.Rows.Add("Product B", 2000); dt.Rows.Add("Product C", 3000); dt.Rows.Add("Product D", 4000); dt.Rows.Add("Product E", 5000); // Calculate the total sales int totalSales = 0; foreach (DataRow row in dt.Rows) { totalSales += Convert.ToInt32(row["Sales"]); } // Calculate the percentage of total sales for each product foreach (DataRow row in dt.Rows) { double percentage = (Convert.ToInt32(row["Sales"]) / (double)totalSales) * 100; Console.WriteLine($"{row["Product"]}: {percentage:F2}%"); } } } ```

```csharp using System; using System.Collections.Generic; using System.Linq; public class ProductSales { public string ProductName { get; set; } public decimal Sales { get; set; } } public class SalesCalculator { public Dictionary<string, decimal> CalculateProductSalesPercentage(List<ProductSales> productSales) { // Calculate total sales decimal totalSales = productSales.Sum(ps => ps.Sales); // Calculate percentage of total sales for each product var productSalesPercentages = productSales.ToDictionary( ps => ps.ProductName, ps => (ps.Sales / totalSales) * 100); return productSalesPercentages; } } class Program { static void Main() { var salesCalculator = new SalesCalculator(); var productSales = new List<ProductSales> { new ProductSales { ProductName = "Product A", Sales = 1000 }, new ProductSales { ProductName = "Product B", Sales = 2000 }, new ProductSales { ProductName = "Product C", Sales = 3000 }, }; var productSalesPercentages = salesCalculator.CalculateProductSalesPercentage(productSales); foreach (var productSalesPercentage in productSalesPercentages) { Console.WriteLine($"{productSalesPercentage.Key}: {productSalesPercentage.Value:F2}%"); } } } ``` This C# code calculates the percentage of total sales each product represents. It defines a `ProductSales` class to hold the product name and sales amount, and a `SalesCalculator` class with a method to calculate the sales percentages. Here's a step-by-step explanation: 1. **Define the data model**: The `ProductSales` class represents a product with its name and sales amount. 2. **Create a sales calculator**: The `SalesCalculator` class contains a method `CalculateProductSalesPercentage` that takes a list of `ProductSales` objects as input. 3. **Calculate total sales**: The method calculates the total sales by summing up the sales amounts of all products using LINQ's `Sum` method. 4. **Calculate sales percentages**: It then calculates the percentage of total sales for each product by dividing the product's sales amount by the total sales and multiplying by 100. The results are stored in a dictionary with the product name as the key. 5. **Example usage**: In the `Main` method, an instance of `SalesCalculator` is created, and a list of `ProductSales` objects is defined. The `CalculateProductSalesPercentage` method is called, and the resulting dictionary is iterated over to print the sales percentages for each product. The code uses LINQ for concise data processing and follows standard C# naming conventions and coding practices. The example usage demonstrates how to use the `SalesCalculator` class to calculate and display the sales percentages for a given set of products.