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CSharp · Console

/Program.cs

using System;
using System.Collections.Generic;

public class Program
{
	public static void Main()
	{
		var Persons = new List<Person>();
		Persons.Add(new Person("Eric"));
		Persons[0].Childs = new List<Person>();
		Persons[0].Childs.Add(new Person("Tom"));
		Persons[0].Childs.Add(new Person("John"));
		Persons[0].Childs[0].Childs = new List<Person>();
		Persons[0].Childs[0].Childs.Add(new Person("Bill"));
		Persons.Add(new Person("John"));
		
		DisplayPerson(Persons);
	}

	public class Person
	{
		public Person(string name)
		{
			this.Name = name;
		}

		public string Name {get;set;}
		public List<Person> Childs{get;set;}
	}

	public static void DisplayPerson(List<Person> persons)
	{
		if (persons != null)
		{
			Stack<Person> personStack = new Stack<Person>();
			int level = 1;
			persons.ForEach(personStack.Push);
			while (personStack.Count > 0)
			{
				Person item = personStack.Pop();
				Console.WriteLine("-" + item.Name + ", Level:" + level); 
				if (item.Childs != null)
				{
					item.Childs.ForEach(personStack.Push);
					level++;
				}
			}
		}
	}
}