using static System.Console;

using System.Diagnostics;

public class Program {

    public static void Main() {

        var x = "";

        var sw = new Stopwatch();

        sw.Start();

        for (var i = 0; i < 10000; i++) {

            x = string.Format("teste de string formatada com resultado: {0}", i + 5);

        }

        sw.Stop();

        WriteLine(sw.ElapsedTicks);

        sw.Restart();

        for (var i = 0; i < 10000; i++) {

            x = $"teste de string formatada com resultado: {i + 5}";

        }

        sw.Stop();

        WriteLine(sw.ElapsedTicks);

    }

}