#include <iostream>
#include <string>
#include <algorithm>
using namespace std;
class BigInt
{
private:
    int *digits = new int[10];
    int amount;
    string zn;
public:
    void  input(){
        string num, zn;
        cout << "Введите знак числа" << endl;
        cin >> zn;
        cout << "Введите число" << endl;
        cin >> num;
        input(num, zn);;
    }
    string getZn(){
        return zn;
    }
    void input(string s, string zn1)
    {
        string str = s;
        zn = zn1;
        int pos = 0;
        for (int i = str.size() - 1; i >= 0; i--)
            digits[pos++] = str[i] - '0';
        amount = str.size();
    }
    BigInt(int num1) {
        string num = "";
        if (num1 < 0) zn = "-";
        else zn = "+";
        num = num1;
        input(num, zn);
    }
    BigInt() {
        string num = "57";
        input(num, "+");
    }
    BigInt(string s, string zn1) {
        input(s, zn1);
    }
    void output()
    {
        cout << zn;
        for (int i = amount - 1; i >= 0; i--)
            cout << digits[i];
    }
    friend bool operator > (BigInt &a, BigInt &b) {
        if(a.zn=="-" && b.zn=="-"){
            if (a.amount != b.amount)
            return b.amount>b.amount;
            for (int i = a.amount - 1; i >= 0; i--)
            {
                if (a.digits[i] != b.digits[i])
                    return b.digits[i]>a.digits[i];
            }
            return false;
        }
        else{
            if (a.amount != b.amount)
            return a.amount>b.amount;
            for (int i = a.amount - 1; i >= 0; i--)
            {
                if (a.digits[i] != b.digits[i])
                    return a.digits[i]>b.digits[i];
            }
            return false;
        }
    }
    friend bool operator < (BigInt &a, BigInt &b) {
        if(a.zn=="-" && b.zn=="-"){
            if (a.amount != b.amount) return b.amount<a.amount;
            for (int i = a.amount - 1; i >= 0; i--)
            {
                if (a.digits[i] != b.digits[i])
                    return b.digits[i]<a.digits[i];
            }
            return false;
        }
        else{
            if (a.amount != b.amount) return a.amount<b.amount;
            for (int i = a.amount - 1; i >= 0; i--)
            {
                if (a.digits[i] != b.digits[i])
                    return a.digits[i]<b.digits[i];
            }
            return false;
        }
    }


    BigInt plus(BigInt &a, BigInt &b)
    {
        BigInt res;
        res.amount = max(a.amount, b.amount);
        int r = 0;
        for (int i = 0; i < res.amount; i++)
        {
            if (i >= min(a.amount, b.amount)) {
                if (res.amount == a.amount) b.digits[i] = 0;
                else a.digits[i] = 0;
            }
            res.digits[i] = a.digits[i] + b.digits[i] + r;
            if (res.digits[i] >= 10)
            {
                res.digits[i] -= 10;
                r = 1;
            }
            else
                r = 0;
            if (i == res.amount - 1)
            {
                i++;
                res.digits[i] = r;
            }
        }
        if (res.digits[res.amount])
            res.amount++;
        if (a.zn == b.zn && (a.zn == "+")) res.zn = "+";
        else if (a.zn == b.zn && (a.zn == "-")) res.zn = "-";
        else res.zn = "+";
        return res;
    }
    BigInt minus(BigInt &a, BigInt &b)
    {
        BigInt res;
        bool isMinus = false;
        if (a < b) {
            isMinus = true;
        }
        if (max(a.amount, b.amount) == a.amount && b < a) {
            res = a;
        }
        else {
            res = b;
            swap(a, b);
        }
        if (a.zn == "-" && b.zn == "-" && b < a) isMinus = false;
        if (isMinus) res.zn = "-";
        else res.zn = "+";
        int r = 0;
        for (int i = 0; i < res.amount; i++)
        {
            if (i >= min(a.amount, b.amount)) {
                if (res.amount == a.amount) b.digits[i] = 0;
                else a.digits[i] = 0;
            }
            res.digits[i] -= b.digits[i] + r;
            if (res.digits[i] < 0)
            {
                res.digits[i] += 10;
                res.digits[i + 1]--;
            }
        }
        int pos = res.amount;
        while (pos && !res.digits[pos])
            pos--;
        res.amount = pos + 1;
        res.amount--;
        return res;
    }
    friend void operator++(BigInt &a){
        if (a.zn == "+") a.zn = "-";
        else a.zn = "+";
    }

    friend BigInt operator+(BigInt &a, BigInt &b){
        if (a.zn == b.zn && (a.zn == "+" || a.zn == "-")) {
            return a.plus(a, b);
        }
        else if (a.zn == "+" && b.zn == "-") {
            b.zn = "+";
            return a.minus(a, b);
        }
        else if (a.zn == "-" && b.zn == "+") {
            a.zn="+";
            return a.minus(b, a);
        }
    }
    friend BigInt operator-(BigInt &a, BigInt &b)
    {
        if (a.zn == b.zn && a.zn == "+") {
            return a.minus(a, b);
        }
        else if (a.zn == "+" && b.zn == "-") {
            return a.plus(a, b);
        }
        else if (a.zn == "-" && b.zn == "+") {
            return a.minus(a, b);
        }
        else if (a.zn == "-" && b.zn == "-") {
            b.zn = "+";
            return a.minus(b, a);
        }
    }
    friend BigInt operator*(BigInt &a, BigInt &b)
    {
        BigInt res;
        int temp1 = 10;
        if (a < b) swap(a, b);

        BigInt temp = a;
        for (int j = 0; j < b.amount; j++){
            for (int i = 0; i < b.digits[j] - 1; i++){
                res = a.plus(a, temp);
                temp = res;
            }
            b.digits[j + 1] *= temp1;
            temp1 *= 10;
        }

        if (a.zn == b.zn) res.zn = "+";
        else res.zn = "-";
        return res;
    }
    friend BigInt operator/(BigInt &a, BigInt &b)
    {
        string zn1 = "+";
        if (a.zn != b.zn) zn1 = "-";
        BigInt res("25", "+"), res1("1", "+");
        int temp1 = 0;
        int k = 0;
        if (a < b) swap(a, b);
        BigInt temp = a;
        while (res > res1){
            int f = 0;
            res = a.minus(temp, b);
            temp = res;
            temp1++;
            for (int i = 0; i < res.amount; i++){
                if (res.digits[i] == 0) f++;
            }
            if (f == res.amount) break;
        }
        if (a.zn == b.zn) cout << zn1 << temp1 << endl;
        else cout << zn1 << temp1 << endl;
        return res;
    }

};

int main()
{
    setlocale(LC_ALL, "Russian");
    BigInt bg("50", "+"), bg1("5", "+"), bg2;
    cout << "Введите 1 для суммы, 2-разности, 3-умножения, 4-деления, 5-сравнения, 6-смены знака, 0-выход" << endl;
    int i;
    cin >> i;
    while (i != 0){
        if (i == 1){
            BigInt bg;
            BigInt bg1;
            BigInt bg2;
            bg.input();
            bg1.input();
            cout << "Сумма: ";
            bg2 = bg + bg1;
            bg2.output();
            cout << endl;
        }
        if (i == 2){
            BigInt bg;
            BigInt bg1;
            BigInt bg2;
            bg.input();
            bg1.input();
            cout << "Разность: ";
            bg2 = bg - bg1;
            bg2.output();
            cout << endl;
        }
        if (i == 3){
            BigInt bg;
            BigInt bg1;
            BigInt bg2;
            bg.input();
            bg1.input();
            cout << "Умножение: ";
            bg2 = bg*bg1;
            bg2.output();
            cout << endl;
        }
        if (i == 4){
            BigInt bg;
            BigInt bg1;
            BigInt bg2;
            bg.input();
            bg1.input();
            cout << "Деление: ";
            bg2 = bg / bg1;
        }
        if (i == 5){
            BigInt bg;
            BigInt bg1;
            bg.input();
            bg1.input();
            cout << "Сравнение: ";
            ++bg;
            if ((bg < bg1) == true) cout << "Первое число больше";
            else cout << "Второе число больше";
        }
        if (i == 6){
            BigInt bg;
            bg.input();
            cout << "Смена знака: ";
            ++bg;
            bg.output();
        }
        cin >> i;
    }
}