public class Context {
   static Str X,Y,U;
   static int i,k;
   static void F(Str Z) {
     Z.field = k+1;
   }
   static void  G(Str R) {
    if (k!=0) F(R); 
   }
   public static void main (String args[]) {
     X = new Str(); Y =  new Str();
     if (i == 0) F(X); else G(Y);
     G(U);
   }
} //Context

class Str {
   int field;
}
