using System; class Test { staticvoid Swap(refint x, refint y) { int temp = x; x = y; y = temp; } staticvoid Swap( int x, int y) { int temp = x; x = y; y = temp; } staticvoid Main() { int i =1, j =2; Swap(ref i, ref j); int a =3 , b =99 ; Swap ( a, b ) ; Console.WriteLine("{0} {1}", i, j); // Outputs "2 1" Console.WriteLine("{0} {1}", a , b ); // Outputs "2 1" } }