C# - elegant way of partitioning a list?

Question

I\'d like to partition a list into a list of lists, by specifying the number of elements in each partition.

For instance, suppose I have the list {1, 2, ... 11}, and

Answer 1

You could use an extension method:

public static IList> Partition(this IEnumerable input, Func partitionFunc)
{
      Dictionary partitions = new Dictionary>();


  object currentKey = null;
  foreach (T item in input ?? Enumerable.Empty())
  {
      currentKey = partitionFunc(item);

      if (!partitions.ContainsKey(currentKey))
      {
          partitions[currentKey] = new HashSet();
      }

      partitions[currentKey].Add(item);
  }

  return partitions.Values.ToList();


}