#include<string.h>
#include<stdio.h>
#include<iostream>
using namespace std;
class Expression
{
public:
    virtual void print() = 0;
    virtual Expression *diff() = 0;
};
class Number : public Expression
{
private:
    double x;

public:
    Number(double q)
    {
        x = q;
    }
    Expression *diff()
    {
        return new Number(0);
    }
    void print()
    {
        cout << x;
    }
    ~Number()
    {}
};
class Variable : public Expression
{
private:
    char x,y;

public:
    Variable(char p, char t)
    {
        x=p;
        y = t;

    }
    Expression *diff()
    {
        if (x == y) return new Number(1); else return new Number(0);
    }
    void print()
    {
        cout << x;
    }
    ~Variable()
    {}
};
class Add : public Expression
{
private:
    Expression *r1, *r2;

public:
    Add(Expression*ru, Expression*ri)
    {
        r1 = ru;
        r2 = ri;
    }
    Expression *diff()
    {
        return new Add(r1->diff(), r2->diff());
    }
    void print()
    {
        cout << "(";
        r1->print();
        cout << ")";
        cout << "+";
        r2->print();
    }
    ~Add()
    {}
};
class Sub : public Expression
{
private:
    Expression *f1, *f2;

public:
    Sub(Expression *qu, Expression *qi) : f1(qu), f2(qi)
    {}
    Expression *diff()
    {
        return new Sub(f1->diff(), f2->diff());
    }
    void print()
    {
        cout << "(";
        f1->print();
        cout << ")";
        cout << "-";
        f2->print();
    }
};
class Mul : public Expression
{
private:
    Expression *r1, *r2;

public:
    Mul(Expression*ru, Expression*ri)
    {
        r1 = ru;
        r2 = ri;
    }
    Expression *diff()
    {
        return new Add(new Mul(r1->diff(), r2), new Mul(r1, r2->diff()));
    }
    void print()
    {
        cout << "(";
        r1->print();
        cout << ")";
        cout << "*";
        r2->print();
    }
    ~Mul()
    {}
};
class Div : public Expression
{
private:
    Expression *r1, *r2;

public:
    Div(Expression*ru, Expression*ri)
    {
        r1 = ru;
        r2 = ri;
    }
    Expression *diff()
    {
        return new Div(new Sub(new Mul(r1->diff(), r2), new Mul(r1, r2->diff())), new Mul(r2, r2));
    }
    void print()
    {
        cout << "(";
        r1->print();
        cout << ")";
        cout << "/";
        cout << "(";
        r2->print();
        cout << ")";
    }
    ~Div()
    {}
};
class Pow : public Expression
{
private:
    Expression *r1, *r2;

public:
    Pow(Expression*ru, Expression*ri)
    {
        r1 = ru;
        r2 = ri;
    }
    Expression *diff()
    {
        return new Mul(r2, new Pow(r1, new Sub(r2, new Number(1))));
    }
    void print()
    {
        cout << "(";
        r1->print();
        cout << ")";
        cout << "^";
        cout << "(";
        r2->print();
        cout << ")";
    }
    ~Pow()
    {}
};
class Ln : public Expression
{
private:
    Expression *r1;

public:
    Ln(Expression*ru)
    {
        r1 = ru;
    }
    Expression *diff()
    {
        return new Mul(r1->diff(), new Div(new Number(1), r1));
    }
    void print()
    {
        cout << "Ln(";
        r1->print();
        cout << ")";
    }
    ~Ln()
    {}
};
int main()
{
    Expression* v = new Add(new Variable('x','y'), new Variable('y', 'y'));
    v->print();
    Expression* f = v->diff();
    cout << endl;
    f->print();
    system("pause");
    return 1;

}