 			
 				//expr_print(res);
 				
-			if(neuron_k->maxpool_uexpr==NULL){
+			if(neuron_k->maxpool_uexpr==nullptr){
 				mul_expr = (expr_t *)malloc(sizeof(expr_t));
-				mul_expr->inf_coeff = res->sup_coeff = NULL;
-				mul_expr->dim = NULL;
+				mul_expr->inf_coeff = res->sup_coeff = nullptr;
+				mul_expr->dim = nullptr;
 				mul_expr->size = 0;
 				mul_expr->type = SPARSE;
 				//printf("lb: %g %g\n");

	}
	
	free(fp->layers);
	fp->layers = NULL;
	free(fp->input_inf);
	fp->input_inf = NULL;
        if(fp->input_lexpr!=NULL && fp->input_uexpr!=NULL){
		for(i=0; i < fp->num_pixels; i++){
			free(fp->input_lexpr[i]);
			free(fp->input_uexpr[i]);
		}
	
		free(fp->input_lexpr);
		fp->input_lexpr = NULL;
		free(fp->input_uexpr);
		fp->input_uexpr = NULL;
        }
	free(fp->input_sup);
	fp->input_sup = NULL;
	free(fp->out->output_inf);
	fp->out->output_inf = NULL;
	free(fp->out->output_sup);
	fp->out->output_sup = NULL;
	free(fp->out->lexpr);
	fp->out->lexpr = NULL;
	free(fp->out->uexpr);
	fp->out->uexpr = NULL;
	free(fp->out);
	fp->out=NULL;
	free(fp);
	fp = NULL;
}



		}
		elina_linexpr0_set_coeff_interval_double(res,k,-expr->inf_coeff[j],expr->sup_coeff[j]);
	}
	if((fp->input_lexpr!=nullptr) && (fp->input_uexpr!=nullptr)){
		free_expr(expr);
	}
	return res;
