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/**
 *  @file   add.h
 *  @author SymEngine Developers
 *  @date   2021-02-25
 *  @brief  Classes and functions relating to the binary operation of addition
 *
 *  Created on: 2012-07-11
 *
 *  This file contains the basic binary operations defined for symbolic enties.
 *   In particular the @ref Add class for representing addition is
 *   @b declared here, along with the `add` and `substract` functions.
 */

#ifndef SYMENGINE_ADD_H
#define SYMENGINE_ADD_H

    /**
     *  @brief Create an appropriate instance from dictionary quickly.
     *  @pre The dictionary must be in canonical form.
     *  @see `Mul` for how `Pow` gets returned.
     *  @see `Basic` for the guarantees and expectations.
     *  @param coef the numeric coefficient.
     *  @param d the dictionary of the expression without the coefficient.
     *  @return `coef` if the dictionary is empty (size 0).
     *  @return `Mul` if the dictionary has one element which is a `Mul`.
     *  @return `Integer` if the dictionary has one element which is a
     *   `Integer`.
     *  @return `Symbol` if the dictionary has one element which is a `Symbol`.
     *  @return `Pow` if the dictionary has one element which is a `Pow`.
     *  @return `Add` if the size of the dictionary is greater than 1.
     */
    static RCP<const Basic> from_dict(const RCP<const Number> &coef,
                                      umap_basic_num &&d);

/**
 *  @details This function ensures that each term in *dict* is in canonical
 *   form. The implementation in the form of a exclusion list (defaults to
 *   true).
 *
 *  @note **Canonical form** requires the existance of both `coef` and
 *   `dict`, so `null` coefficients and purely numerical (empty dictionaries)
 *   are also not considered to be in canonical form. Also, the ordering is
 *   important, it must be `(coeff, dict)` and **not** `(dict, coeff)`.
 *
 *  Some **non-cannonical** forms are:
 *   - @f$0 + x@f$.
 *   - @f$0 + 2x@f$.
 *   - @f$ 2 \times 3 @f$.
 *   - @f$ x \times 0 @f$.
 *   - @f$ 1 \times x @f$ has the wrong order.
 *   - @f$ 3x \times 2 @f$ is actually just @f$6x@f$.
 */
bool Add::is_canonical(const RCP<const Number> &coef,
                       const umap_basic_num &dict) const

"""
This function adds two numbers
"""
def sum(a,b):
    return a*b