calc

#include "pch.h"
#include <iostream>
#include <string>
#include <cmath>

using namespace std;

const string alph = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
int E = 5;

string replace(string in)
{
    int k;

    if (in.length() % 2 == 0)
        k = in.length() / 2;
    else
        k = in.length() / 2 + 1;
    for (int i = 0; i < k; i++)
    {
        swap(in[i], in[in.length() - i - 1]);
    }
    return in;
}

char find_symbol(int a)
{
    return alph[a];
}

int find_number(char a)
{
    int i = 0;

    while (a != alph[i])
    {
        i++;
        //cout << i << " ";
    }
    return i;
}

int to_ten_base(string first, int osn)
{
    int second = 0;
    int k = 1;

    while (k <= first.length())
    {
        second += find_number(first[k - 1]) * pow(osn, (first.length() - k));
        k++;
    }
    return second;
}

string to_x_base(int ten, int out)
{
    int x;
    string res;
    while ((ten / out) > 0)
    {
        x = ten % out;
        res = find_symbol(x) + res;
        ten = ten / out;
    }
    res = find_symbol(ten) + res;
    return res;
}

char sravn(string a, string b)
{

    if (a.length() > b.length())
        return '>';
    else if (a.length() < b.length())
        return '<';
    else
    {
        for (int i = 0; i < a.length(); i++)
        {
            if (a[i] > b[i])
            {
                return '>';
            }
            else if (a[i] < b[i])
            {
                return '<';
            }
        }
        return '=';
    }
}

string sum(string a, string b, int osn)
{
    string summed;
    int buf = 0;
    int x = 0, i;

    a = replace(a);
    b = replace(b);

    if (a.length() > b.length())
    {
        for (i = b.length(); i < a.length(); i++)
        {
            b = b + '0';
        }
    }
    else if (b.length() > a.length())
    {
        for (i = a.length(); i < b.length(); i++)
        {
            a = a + '0';
        }
    }
    a += '0';
    b += '0';

    for (i = 0; i < a.length(); i++)
    {
        x = find_number(a[i]) + find_number(b[i]) + buf;

        if (x >= osn)
        {
            buf = 1;
            x = x - osn;
        }
        else
        {
            buf = 0;
        }
        summed = summed + find_symbol(x);
    }

    i = summed.length() - 1;
    if (to_ten_base(summed, osn) != 0)
    {
        while (summed[i] == '0')
        {
            summed.erase(i, 1);
            i--;
        }
    }
    else
        summed = '0';
    summed = replace(summed);
    return summed;
}

string proizv(string a, string b, int n)
{
    string x;
    int kolvo = to_ten_base(b, n);

    if (to_ten_base(a, n) == 0 || to_ten_base(b, n) == 0)
    {
        x = '0';
        return x;
    }

    for (int i = 0; i < kolvo; i++)
    {
        x = sum(x, a, n);
    }
    return x;
}

string difference(string a, string b, int osn)
{
    string diff;
    bool flag = 0;
    int x = 0, i, buf = 0, k = 0;

    a = replace(a);
    b = replace(b);

    if (a.length() > b.length())
    {
        for (i = b.length(); i < a.length(); i++)
        {
            b = b + '0';
        }
    }
    else if (b.length() > a.length())
    {
        for (i = a.length(); i < b.length(); i++)
        {
            a = a + '0';
        }
    }

    for (i = 0; i < a.length(); i++)
    {
        x = find_number(a[i]) - find_number(b[i]) - buf;

        if (x < 0)
        {
            x = x + osn;
            buf = 1;
        }
        else
        {
            buf = 0;
        }
        diff = diff + find_symbol(x);
    }

    i = diff.length() - 1;
    if (to_ten_base(diff, osn) != 0)
    {
        while (diff[i] == '0')
        {
            diff.erase(i, 1);
            i--;
        }
    }
    else
        diff = '0';
    diff = replace(diff);
    return diff;
}

string del(string a, string b, int n)
{
    string x;
    int answer = 0, k = 0;
    bool flag = 0;

    while (to_ten_base(a, n) >= to_ten_base(b, n))
    {
        a = difference(a, b, n);
        answer++;
    }
    x = to_x_base(answer, n);
    return x;
}

string del_s_ost(string a, string b, int n)
{
    string x, na = to_x_base(n, n), chastn, kolvo;
    int answer = 0, k = 0;
    bool flag = 0;

    while (to_ten_base(a, n) >= to_ten_base(b, n))
    {
        a = difference(a, b, n);
        answer++;
    }

    x = to_x_base(answer, n);

    if (to_ten_base(a, n) != 0)
    {

        if (E > 0)
            x = x + ".";

        while (to_ten_base(a, n) != 0 && k < E)
        {
            a = a + '0';
            chastn = del(a, b, n);

            x = x + chastn;

            if (to_ten_base(a, n) >= to_ten_base(b, n))
            {
                kolvo = del(a, b, n);
                a = difference(a, proizv(kolvo, b, n), n);
            }
            if (to_ten_base(proizv(chastn, b, n), n) == n)
                break;
            k++;
        }
    }

    return x;
}

int main()
{
    string one, two, one10, two10, in1, in2;
    int dex, first, second;
    char otvet, task;
    bool sign_first = 0, sign_second = 0;

    setlocale(LC_ALL, "Russian");

    cout << "Введите число a: ";
    cin >> in1;
    cout << "Введите число b: ";
    cin >> in2;
    cout << "Введите операцию: ";
    cin >> task;
    cout << "Введите основание —— , в которой будет проводитьс¤ операци¤: ";
    cin >> dex;

    if (in1[0] == '-')
    {
        in1.erase(0, 1);
        sign_first = 1;
    }
    first = to_ten_base(in1, 10);

    if (in2[0] == '-')
    {
        in2.erase(0, 1);
        sign_second = 1;
    }
    second = to_ten_base(in2, 10);

    one10 = to_x_base(first, 10);
    two10 = to_x_base(second, 10);
    one = to_x_base(first, dex);
    two = to_x_base(second, dex);

    switch (task)
    {
    case '+':
    {
        if (one10 == two10)
        {
            if (sign_first == 1 && sign_second == 0)
                cout << "-" << one << " + " << two << " = 0 = 0" << endl;
            else if (sign_first == 0 && sign_second == 1)
                cout << one << " + (-" << two << ") = 0 = 0" << endl;
            else if (sign_first == 1 && sign_second == 1)
                cout << "-" << one << " + (-" << two << ") = -" << sum(one, two, dex) << " = -" << to_ten_base(sum(one, two, dex), dex) << endl;
            else
                cout << one << " + " << two << " = " << sum(one, two, dex) << " = " << to_ten_base(sum(one, two, dex), dex) << endl;
        }
        else if (one10 > two10)
        {
            if (sign_first == 1)
            {
                if (sign_second == 1)
                    cout << "-" << one << " + (-" << two << ") = -" << sum(one, two, dex) << " = -" << to_ten_base(sum(one, two, dex), dex) << endl;
                else
                    cout << "-" << one << " + " << two << " = -" << difference(one, two, dex) << " = -" << to_ten_base(difference(one, two, dex), dex) << endl;
            }
            else
            {
                if (sign_second == 1)
                    cout << one << " + (-" << two << ") = -" << difference(one, two, dex) << " = -" << to_ten_base(difference(one, two, dex), dex) << endl;
                else
                    cout << one << " + " << two << " = " << sum(one, two, dex) << " = " << to_ten_base(sum(one, two, dex), dex) << endl;
            }
        }
        else
        {
            if (sign_first == 1)
            {
                if (sign_second == 1)
                    cout << "-" << one << " + (-" << two << ") = -" << sum(one, two, dex) << " = -" << to_ten_base(sum(one, two, dex), dex) << endl;
                else
                    cout << "-" << one << " + " << two << " = " << difference(two, one, dex) << " = " << to_ten_base(difference(two, one, dex), dex) << endl;
            }
            else
            {
                if (sign_second == 1)
                    cout << one << " + (-" << two << ") = -" << difference(two, one, dex) << " = -" << to_ten_base(difference(two, one, dex), dex) << endl;
                else
                    cout << one << " + " << two << " = " << sum(one, two, dex) << " = " << to_ten_base(sum(one, two, dex), dex) << endl;
            }
        }
        break;
    }
    case '-':
    {
        if (one10 == two10)
        {
            if (sign_first == 0 && sign_second == 0)
                cout << one << " - " << two << " = 0 = 0" << endl;
            else if (sign_first == 1 && sign_second == 0)
                cout << "-" << one << " - " << two << " = " << sum(one, two, dex) << " = -" << to_ten_base(sum(one, two, dex), dex) << endl;
            else if (sign_first == 0 && sign_second == 1)
                cout << one << " - (-" << two << ") = " << sum(one, two, dex) << " = " << to_ten_base(sum(one, two, dex), dex) << endl;
            else
                cout << "-" << one << " - (-" << two << ") = 0 = 0" << endl;

        }
        else if (one10 > two10)
        {
            if (sign_first == 1)
            {
                if (sign_second == 1)
                {
                    cout << "-" << one << " - (-" << two << ") = " << difference(two, one, dex) << " = " << to_ten_base(difference(two, one, dex), dex) << endl;
                }
                else
                    cout << "-" << one << " - " << two << " = -" << sum(one, two, dex) << " = -" << to_ten_base(sum(one, two, dex), dex) << endl;
            }
            else
            {
                if (sign_second == 1)
                    cout << one << " - (-" << two << ") = " << sum(one, two, dex) << " = " << to_ten_base(sum(one, two, dex), dex) << endl;
                else
                    cout << one << " - " << two << " = " << difference(one, two, dex) << " = " << to_ten_base(difference(one, two, dex), dex) << endl;
            }
        }
        else
        {
            if (sign_first == 1)
            {
                if (sign_second == 1)
                    cout << "-" << one << " - (-" << two << ") = -" << difference(one, two, dex) << " = -" << to_ten_base(difference(one, two, dex), dex) << endl;
                else
                    cout << "-" << one << " - " << two << " = -" << sum(one, two, dex) << " = -" << to_ten_base(sum(one, two, dex), dex) << endl;
            }
            else
            {
                if (sign_second == 1)
                    cout << one << " - (-" << two << ") = " << sum(one, two, dex) << " = " << to_ten_base(sum(one, two, dex), dex) << endl;
                else
                    cout << one << " - " << two << " = -" << difference(two, one, dex) << " = -" << to_ten_base(difference(two, one, dex), dex) << endl;
            }
        }
        break;
    }
    case '*':
    {
        if (to_ten_base(one, 10) == 0 || to_ten_base(two, 10) == 0)
        {
            if (sign_first) cout << "-";
            cout << one << " * ";
            if (sign_second) cout << "-";
            cout << two << " = 0 = 0" << endl;
        }
        else if (sign_first == 1)
        {
            if (sign_second == 1)
                cout << "-" << one << " * (-" << two << ") = " << proizv(one, two, dex) << " = " << to_ten_base(proizv(one, two, dex), dex) << endl;
            else
                cout << "-" << one << " * " << two << " = -" << proizv(one, two, dex) << " = -" << to_ten_base(proizv(one, two, dex), dex) << endl;
        }
        else
        {
            if (sign_second == 1)
                cout << one << " * (-" << two << ") = -" << proizv(one, two, dex) << " = -" << to_ten_base(proizv(one, two, dex), dex) << endl;
            else
                cout << one << " * " << two << " = " << proizv(one, two, dex) << " = " << to_ten_base(proizv(one, two, dex), dex) << endl;
        }
        break;
    }
    case '/':
    {
        cout << "Введите количество знаков после зап¤той: ";
        cin >> E;
        if (to_ten_base(one, 10) == 0 && sign_second == 1)
            cout << " 0 / (-" << two << ") = 0 = 0" << endl;
        else if (to_ten_base(two, dex) == 0)
        {
            cout << "Деление на ноль, звершение работы программы" << endl;
            break;
        }
        else if (sign_first == 1)
        {
            if (sign_second == 1)
                cout << "-" << one << " / (-" << two << ") = " << del_s_ost(one, two, dex) << " = " << del_s_ost(one10, two10, 10) << endl;
            else
                cout << "-" << one << " / " << two << " = -" << del_s_ost(one, two, dex) << " = -" << del_s_ost(one10, two10, 10) << endl;
        }
        else
        {
            if (sign_second == 1)
                cout << one << " / (-" << two << ") = -" << del_s_ost(one, two, dex) << " = -" << del_s_ost(one10, two10, 10) << endl;
            else
                cout << one << " / " << two << " = " << del_s_ost(one, two, dex) << " = " << del_s_ost(one10, two10, 10) << endl;
        }
        break;
    }
    case '?':
    {
        if (sign_first == 1)
        {
            if (sign_second == 1)
                cout << "-" << one << " " << sravn(one, two) << " -" << two << " => -" << to_ten_base(one, dex) << " " << sravn(one, two) << " -" << to_ten_base(two, dex) << endl;
            else
                cout << "-" << one << " < " << two << " => -" << to_ten_base(one, dex) << " < " << to_ten_base(two, dex) << endl;
        }
        else
        {
            if (sign_second == 1)
                cout << one << " > -" << two << " => " << to_ten_base(one, dex) << " > -" << to_ten_base(two, dex) << endl;
            else
                cout << one << " " << sravn(one, two) << " " << two << " => " << to_ten_base(one, dex) << " " << sravn(one, two) << " " << to_ten_base(two, dex) << endl;
        }
        break;
    }
    default:
    {
        cout << "¬веденной операции не существует" << endl;
        break;
    }
    }
    return 0;
}