Duct-typed extension methods Example 11

Example11.cs

// Example 11: add with params

// Use params to take several ints, each representing 3 digits
public static void Add<TKey>(this IDictionary<TKey, int> dictionary, TKey key, params int[] values)
=> dictionary.Add(key, values.Aggregate(0, (s, v) => s*1000 + v));

// Now we can write it like this
var populations = new Dictionary<string, int>
{
  { "China", 1,409,517,397 },
  { "India", 1,339,180,127 },
  { "USA", 324,459,463 },
  { "Indonesia", 263,991,379 },
  { "Brazil", 209,288,278 }
};

// Output each item, to see if things work correctly
foreach(var (key, value) in populations)
{
  Console.WriteLine($"{key}: {value}");
}