Input c# (Doughnut-Problem)

Hello everyone,
First, please excuse my poor English.

I'm really new to programming and spoj.com. I tried to do the Doughnut Problem, but i failed .

I think the main Problem for me is how to use the input. I did it that way, but there is an compiling error.

I would be glad if someone could help me.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace Doughnut
{
    class Program
    {
        static void Main(string[] args)
        {
            int c,k,w;
            string ausgabe="";
            int t = Convert.ToInt32(Console.ReadLine());
            for (int i = 0; i < t; i++)
            {
                string x = Console.ReadLine();
                string[] xa = x.Split(' ');
                c = Convert.ToInt32(xa[0]);
                k = Convert.ToInt32(xa[1]);
                w = Convert.ToInt32(xa[2]);
                if (c * w <= k)
                ausgabe = ausgabe + "yes"+ "\r\n";
            else
                ausgabe = ausgabe + "no" + "\r\n";


        }
        Console.WriteLine(ausgabe);
       
                                                 

        
    }
}
}