using System;

public class Program

{

    public static void Main()

    {

        var a = "01/27/2023";

        var b = "01/07/2023 10:15 AM";

        var c = Convert.ToDateTime(a).Add(Convert.ToDateTime(b).TimeOfDay).ToString("g", System.Globalization.CultureInfo.CreateSpecificCulture("en-us"));

        Console.WriteLine(c);

    }

}