using System;

public class BinTree
{
 public BinTree left;
 public BinTree right;
 public int value;

 public BinTree( int depth )
 {
  value = 1;
  if ( depth <= 1 )
  {
   left = null;
   right = null;
  }
  else
  {
   left = new BinTree( depth - 1 );
   right = new BinTree( depth - 1 );
  }
 }
}

class SumBinTree
{
 public static void Main( String[] args )
 {
  int depth = System.Convert.ToInt32( args [ 0 ] );
  SumBinTree sbt = new SumBinTree();
  BinTree btree = new BinTree( depth );
  sbt.Sum( btree, sbt.c );
  Console.WriteLine( "Sum = " + sbt.Get() );
 }

 int Get() & Channel c( int x ) { return ( x ); }

 movable Sum( BinTree btree, Channel( int ) c )
 {
  if ( btree.left == null )
   c.Send( btree.value );
  else
  {
   SumBinTree sbt = new SumBinTree();
   Sum( btree.left, sbt.c1 );
   Sum( btree.right, sbt.c2 );
   c.Send( sbt.Get2() );
  }
 }

 int Get2() & Channel c1( int x ) & Channel c2( int y )
 {
  return x + y;
 }
}