@Override public String toString(){
  StringBuilder result=new StringBuilder();
  for (  DF_LatticeCell cell : values()) {
    result.append(cell);
    result.append("\n");
  }
  return result.toString();
}

@ Override public String toString ( ) { StringBuilder result = new StringBuilder ( ) ; for ( DF_LatticeCell cell : values ( ) ) { result . append ( cell ) ; result . append ( "\n" ) ; } return result . toString ( ) ; }
return a string representation of the dataflow solution
