using System.IO;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication1
{
     class Program
     {
         static void Main(string[] args)
         {
             int a;
             Console.ReadLine(a); //Выдаёт ошибку
             Console.WriteLine(a);
         }     
     }
}

if (place_meeting(x,y,t_ground))  
x+=0