using System;

using System.Linq;

using System.Collections.Generic;

public class Program

{

    public class Model 

    {

        public string Country;

        public string Region;

        public string Department;

        public string City;

    }

    public static void Main()

    {

        var models = new List<Model> 

        {

            new Model { Country = "France", Region = "FranceRegionA", Department = "FranceDept1", City = "FranceA" },

            new Model { Country = "France", Region = "FranceRegionA", Department = "FranceDept1", City = "FranceB" },

            new Model { Country = "France", Region = "FranceRegionA", Department = "FranceDept2", City = "FranceC" },

            new Model { Country = "France", Region = "FranceRegionB", Department = "FranceDept3", City = "FranceD" },

            new Model { Country = "Italy", Region = "ItalyRegionA", Department = "ItalyDept1", City = "ItalyA" },

            new Model { Country = "Italy", Region = "ItalyRegionA", Department = "ItalyDept2", City = "ItalyB" },

        };

        var countries = models.GroupBy(x => x.Country)

            .Select((x, index) => Tuple.Create(x.Key, new { Id = index + 1 }))

            .ToDictionary(x => x.Item1, x => x.Item2);

        var regions = models.GroupBy(x => x.Region)

            .Select((x, index) => Tuple.Create(x.Key, new { ParentId = countries[x.First().Country].Id, Id = index + 1 }))

            .ToDictionary(x => x.Item1, x => x.Item2);

        var departments = models.GroupBy(x => x.Department)

            .Select((x, index) => Tuple.Create(x.Key, new { ParentId = regions[x.First().Region].Id, Id = index + 1 }))

            .ToDictionary(x => x.Item1, x => x.Item2);

        var cities = models

            .Select((x, index) => Tuple.Create(x.City, new { ParentId = departments[x.Department].Id, Id = index + 1 }))

            .ToDictionary(x => x.Item1, x => x.Item2);

        countries.Dump();

        regions.Dump();

        departments.Dump();

        cities.Dump();

    }

}