public static DictionaryOfLists <K, V> ToDictionaryOfLists <K, V>(this IEnumerable <V> self, Func <V, K> keySelector)
{
var r = new DictionaryOfLists <K, V>();
foreach (var x in self)
{
r.Add(keySelector(x), x);
}
return(r);
}
public static (List <(TKey key, List <TValue> values)> shared, List <(TKey key, TValue value)> unique) SplitByCount <TKey, TValue>(this DictionaryOfLists <TKey, TValue> items)
{
