Console.InputEncoding = Encoding.Unicode;
Console.OutputEncoding = Encoding.Unicode;

bool loopExitFlag = false;

while ( !loopExitFlag )
{
    Console.Write( "a = " );
    string aRaw = Console.ReadLine();
    int a = int.Parse( aRaw );

    Console.Write( "b = " );
    string bRaw = Console.ReadLine();
    int b = int.Parse( bRaw );

    Console.WriteLine( $"a = {a}, b = {b}" );
    Console.WriteLine( $"SWAP" );

    (a, b) = (b, a);

    Console.WriteLine( $"a = {a}, b = {b}\n" );

    Console.WriteLine( "Continue? Enter 'n' for exit" );
    string continueAnswer = Console.ReadLine();
    string exitAnswer = "n";

    loopExitFlag = string.Equals( continueAnswer, exitAnswer );
}