using System;

using System.Collections.Generic;

using System.Linq;

    class Program

    {

        public static List<Human> humans = new List<Human>()

        {

            new Human

            {

                FirstName="Karl",

                LastName="Karlson",

                clothings=new List<Clothing>()

                {

                    new Clothing

                    {

                        Garment="T-Shirt",

                        Color="pink"

                    },

                    new Clothing

                    {

                        Garment="Pant",

                        Color="white"

                    },

                    new Clothing

                    {

                        Garment="Shoes",

                        Color="black"

                    }

                }

            },

            new Human

            {

                FirstName="Paula",

                LastName="Paulson",

                clothings=new List<Clothing>()

                {

                    new Clothing

                    {

                        Garment="T-Shirt",

                        Color="red"

                    },

                    new Clothing

                    {

                        Garment="Pant",

                        Color="blue"

                    },

                    new Clothing

                    {

                        Garment="Shoes",

                        Color="black"

                    },

                    new Clothing

                    {

                        Garment = "RandomGarment", //<- added a new clothing

                        Color = "RandomColor"

                    }

                }

            }

        };

​

        public static List<CurrentClothes> currentclothes = new List<CurrentClothes>()

        {

            new CurrentClothes

            {

                Garment = "Pant",

                Color = "blue"

            },

            new CurrentClothes

            {

                Garment = "T-Shirt",

                Color = "red"

            },

            new CurrentClothes

            {

                Garment = "Shoes",

                Color = "black"

            }

        };

​

        static void Main(string[] args)

        {

            var currentclothesAsHashSet = currentclothes.ToHashSet();

            var human = humans.Where(x => !currentclothesAsHashSet.Except(x.clothings.OfType<CurrentClothes>().ToHashSet()).Any());

            foreach (var human1 in human)

            {

                Console.WriteLine(human1.FirstName);

            }

        }

    }

​

    public class Human

    {

        public string FirstName { get; set; }

        public string LastName { get; set; }

        public List<Clothing> clothings { get; set; }

    }

​

    public class Clothing : CurrentClothes

    {

        public string ClothingID { get; set; }

    }

​

    public class CurrentClothes : IEquatable<CurrentClothes>

    {

        public string Garment { get; set; }

        public string Color { get; set; }

​

        public override bool Equals(object obj) => ReferenceEquals(this, obj) || obj is CurrentClothes other && Equals(other);

        public bool Equals(CurrentClothes other)

        {

            if (ReferenceEquals(null, other)) return false;

            if (ReferenceEquals(this, other)) return true;

            return Garment == other.Garment && Color == other.Color;

        }

        public override int GetHashCode() => HashCode.Combine(Garment, Color);

    }