int a, b, c, x;  
          Console.WriteLine("a= ");  
          a = Console.ReadLine();  
          Console.WriteLine(a);
          Console.WriteLine("b= ");  
          b = Console.ReadLine();  
          Console.WriteLine(b);
          Console.WriteLine("c= ");  
          c = Console.ReadLine();  
          Console.WriteLine(c);
          Console.Read();

            string a, b, c, x;
             Console.WriteLine("a= ");
             a = Console.ReadLine();
             Console.WriteLine(a);
             Console.WriteLine("b= ");
             b = Console.ReadLine();
             Console.WriteLine(b);
             Console.WriteLine("c= ");
             c = Console.ReadLine();
             Console.WriteLine(c);
             Console.Read();

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

namespace ConsoleApplication1
{
     class Program
     {
         static void Main(string[] args)
         {
             string a, b;
             System.Console.WriteLine("Введите первое число:");
             a = System.Console.ReadLine();
             System.Console.WriteLine("Введите второе число:");
             b = System.Console.ReadLine();
             System.Console.Write(a+"+"+b+"=");
             System.Console.Write(System.Convert.ToInt32(a) + System.Convert.ToInt32(b));
             System.Console.ReadKey();
         }
     }
}

public static void main();
{
             int a, b, c;
              
             Console.WriteLine("First: ");
             a = Console.Read();
            
             Console.WriteLine("\nSecond: ");
             b = Console.Read();

             Console.WriteLine("\nThird: ");
             c = Console.Read();
              
             Console.WriteLine(a, b, c);
             Console.ReadKey();
}

#include <iostream> // это необходимо для std::cout и std::endl и для перегруженного оператора <<
   
int main()
{
     std::cout << "Hello, world!" << std::endl;
     return 0;
}

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

namespace ConsoleApplication1
{
     class Program
     {
         static void Main(string[] args)
         {
             System.Console.WriteLine("Привет, мир");
         }
     }
}

unit Unit1;  

{$mode objfpc}{$H+}

interface

uses
   Classes, SysUtils, FileUtil, Forms, Controls, Graphics, Dialogs;  

type
   TForm1 = class(TForm)
   private
     { private declarations }
   public
     { public declarations }
   end;  

var
   Form1: TForm1;  

implementation

{$R *.lfm}

end.   

program Project1;

{$mode objfpc}{$H+}

uses
   {$IFDEF UNIX}{$IFDEF UseCThreads}
   cthreads,
   {$ENDIF}{$ENDIF}
   Classes, SysUtils, CustApp
   { you can add units after this };

type

   { TMyApplication }

   TMyApplication = class(TCustomApplication)
   protected
     procedure DoRun; override;
   public
     constructor Create(TheOwner: TComponent); override;
     destructor Destroy; override;
     procedure WriteHelp; virtual;
   end;

{ TMyApplication }

procedure TMyApplication.DoRun;
var
   ErrorMsg: String;
begin
   // quick check parameters
   ErrorMsg:=CheckOptions('h','help');
   if ErrorMsg<>'' then begin
     ShowException(Exception.Create(ErrorMsg));
     Terminate;
     Exit;
   end;

   // parse parameters
   if HasOption('h','help') then begin
     WriteHelp;
     Terminate;
     Exit;
   end;

   { add your program here }

   // stop program loop
   Terminate;
end;

constructor TMyApplication.Create(TheOwner: TComponent);
begin
   inherited Create(TheOwner);
   StopOnException:=True;
end;

destructor TMyApplication.Destroy;
begin
   inherited Destroy;
end;

procedure TMyApplication.WriteHelp;
begin
   { add your help code here }
   writeln('Usage: ',ExeName,' -h');
end;

var
   Application: TMyApplication;

{$R *.res}

begin
   Application:=TMyApplication.Create(nil);
   Application.Title:='My Application';
   Application.Run;
   Application.Free;
end.          

program Project1;

{$APPTYPE CONSOLE}

begin

end.