public Pair Add(Pair p1, Pair p2) { Pair result =new Pair(); result.First = p1.First + p2.First; result.Second = p1.Second + p2.Second; return result; }
public Pair Substract(Pair p1, Pair p2) { Pair result=new Pair(); result.First = p1.First - p2.First; result.Second = p1.Second - p2.Second; return result; }