Using signs + and - for swapping of two values.
using system;
namespace TestConsole
{
class Program
{
static void Main()
{
int a = 10; int b = 20;
Console.write("After swap a = {0} and b = {1}", a, b); a = a + b - (b = a);
Console.Write("After swap a = {0} and b = {1}", a, b);
}
}
}