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CSharp · Console

/Program.cs

using System;
using System.Collections.Generic;
using System.Linq;
					
public class Program
{
	public static void Main()
	{
		int[] x = new int[] {1, 2, 3, 4, 5, 6, 7, 8}; // <~~~ var retorno = db.retornoDb.Tolist()
		int[] t = new int[] {500, 501, 502, 503};   // <~~~ int[] IdTecnico
		int xn = t.Length;

		Dictionary<int, List<int>> tecnicosDivididos = new Dictionary<int, List<int>>();

		// inicializa os itens no dicionario
		foreach(int T in t) {
			tecnicosDivididos.Add(T, new List<int>());
		}

		for(int i = 0; i < x.Length; i++) {
			int I = i % xn;
			int name = t[I];
			(tecnicosDivididos[name] as List<int>).Add(x[i]);
		}

		foreach(KeyValuePair<int, List<int>> item in tecnicosDivididos) {
			Console.WriteLine("{0} => {1}", item.Key, string.Join(", ", item.Value));
		}
	}
}