Property initialization

using System;
using System.Collections.Generic;
using System.Linq;

namespace CSharpTest
{

    class Instance
    {
        static int instanceId = 0;
        int id;
        List<int> elems = new List<int>()
        {
            instanceId++,
            instanceId++,
        };
        public Instance()
        {
            id = instanceId++;
        }

        public void PrintIds()
        {
            Console.WriteLine($"id = {id}");
            var idx = 0;
            foreach (var elem in elems) {
                Console.WriteLine($"elem[{idx}] = {elem}");
                idx++;
            }
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            var i1 = new Instance();
            var i2 = new Instance();
            i1.PrintIds();
            i2.PrintIds();
        }
    }
}


/*
Output:

id = 2
elem[0] = 0
elem[1] = 1
id = 5
elem[0] = 3
elem[1] = 4

*/