public String apply(Ast ast){
		decl += ast.getClass().getSimpleName() + "_" + i + " [label=\"" + ast.getClass().getSimpleName() + "\"]\n";
		int n = i++;
		Ast[] objs = ast.getVariables();
		//System.out.println(objs[0] + " " + objs[1]);
		if (objs !=null) {
			for ( int j = 0; j<objs.length; j++){
				if (objs[j] != null){
					String s = apply(objs[j]);
					link += ast.getClass().getSimpleName() + "_" + n + " -> " + s + "\n"; //+ "[label=\"" + obj.getClass().getSimpleName() + "\"]\n";
				}
			}
		}
		return  ast.getClass().getSimpleName() + "_" + n;
	}