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// This is from our Framework, as we're not actually using 

// But this is basically a `Person.Where(x => x.IsActive)` query

// And returns all persons that are active

var people = Querier.Person.AttrQuery(x => x.IsActive).AsQueryable<Person>().ToList()M



// A 2D List, where every inner list is a set of duplicate people

var duplicates = new List<List<Person>> {new List<Person>()};

var last = new Person();



foreach (var person in people)

{

    if (person.Email == last.Email)

        duplicates.Last().Add(person);

    else

        duplicates.Add(new List<Person>());

}



// Remove all empty Lists and all Lists without any duplicates

duplicates = duplicates.Where(x => x.Count > 1).ToList();



// Here is where magic happens, I select all the lists 

duplicates = duplicates

    .SelectMany(x => x)

    .GroupBy(x => x.Email)

    .Select(x => new List<Person>(x.ToList()))

    .ToList();

// This is from our Framework, as we're not actually using 

// But this is basically a `Person.Where(x => x.IsActive)` query

// And returns all persons that are active

var people = Querier.Person.AttrQuery(x => x.IsActive).AsQueryable<Person>().ToList()M



// A 2D List, where every inner list is a set of duplicate people

var duplicates = new List<List<Person>> {new List<Person>()};

var last = new Person();



foreach (var person in people)

{

    if (person.Email == last.Email)

        duplicates.Last().Add(person);

    else

        duplicates.Add(new List<Person>());

}



// Remove all empty Lists and all Lists without any duplicates

duplicates = duplicates.Where(x => x.Count > 1).ToList();



// Here is where magic happens, I select all the lists 

duplicates = duplicates

    .SelectMany(x => x)

    .GroupBy(x => x.Email)

    .Select(x => new List<Person>(x.ToList()))

    .ToList();

// This is from our Framework, as we're not actually using 

// But this is basically a `Person.Where(x => x.IsActive)` query

// And returns all persons that are active

var people = Querier.Person.AttrQuery(x => x.IsActive).AsQueryable<Person>().ToList()M



// A 2D List, where every inner list is a set of duplicate people

var duplicates = new List<List<Person>> {new List<Person>()};

var last = new Person();



foreach (var person in people)

{

    if (person.Email == last.Email)

        duplicates.Last().Add(person);

    else

        duplicates.Add(new List<Person>());

}



// Remove all empty Lists and all Lists without any duplicates

duplicates = duplicates.Where(x => x.Count > 1).ToList();



// Here is where magic happens, I select all the lists 

duplicates = duplicates

    .SelectMany(x => x)

    .GroupBy(x => x.Email)

    .Select(x => new List<Person>(x.ToList()))

    .ToList();

// This is from our Framework, as we're not actually using 

// But this is basically a `Person.Where(x => x.IsActive)` query

// And returns all persons that are active

var people = Querier.Person.AttrQuery(x => x.IsActive).AsQueryable<Person>().ToList()M



// A 2D List, where every inner list is a set of duplicate people

var duplicates = new List<List<Person>> {new List<Person>()};

var last = new Person();



foreach (var person in people)

{

    if (person.Email == last.Email)

        duplicates.Last().Add(person);

    else

        duplicates.Add(new List<Person>());

}



// Remove all empty Lists and all Lists without any duplicates

duplicates = duplicates.Where(x => x.Count > 1).ToList();



// Here is where magic happens, I select all the lists 

duplicates = duplicates

    .SelectMany(x => x)

    .GroupBy(x => x.Email)

    .Select(x => new List<Person>(x.ToList()))

    .ToList();

Your Answer

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