#include <string>
#include <vector>
#include<stdio.h>

class LongInt {
protected:
    std::string number;
public:
    LongInt(const std::string& copy = "");
    ~LongInt(){}

    std::string get_number() const { return number; }
    void set_number(const std::string set);

    LongInt operator=(const LongInt& copy);
    LongInt operator+=(const LongInt& buff);
    friend LongInt operator+(const LongInt& buff1, const LongInt& buff2);
    friend LongInt operator-(const LongInt& buff1, const LongInt& buff2);
    friend LongInt operator*(const LongInt& buff1, const LongInt& buff2);
    friend LongInt operator/(const LongInt& buff1, const LongInt& buff2);
    std::string ToBinary();
    void print();

};

void LongInt::print() {
    printf("%s",number);
}

std::string LongInt::ToBinary() {
    int num1 = 0;
    for (int i = 0; i < number.length(); i++) {
        num1 = num1 * 10 + (number[i] - 48);
    }


    int mod;
    long int double_ = 0;

    for (int i = 0; num1 > 0; i++) {

        mod = num1 % 2;
        num1 = (num1 - mod) / 2;
        double_ += mod * pow((double)10, i);
    }
    return std::to_string(double_);
}

LongInt::LongInt(const std::string& copy) {
    this->number = copy;
}

LongInt LongInt::operator=(const LongInt& copy) {
    this->number = copy.get_number();
    return *this;
}

LongInt LongInt::operator+=(const LongInt& buff) {
    int num1 = 0;
    int num2 = 0;
    for (int i = 0; i < number.length(); i++) {
        num1 = num1 * 10 + (number[i] - 48);
    }
    for (int i = 0; i < buff.get_number().length(); i++) {
        num2 = num2 * 10 + (buff.get_number()[i] - 48);
    }
    num1 += num2;
    this->number = num1;
    return *this;
}

LongInt operator+(const LongInt& buff1, const LongInt& buff2){
    int num1 = 0;
    int num2 = 0;
    for (int i = 0; i < buff1.get_number().length(); i++) {
        num1 = num1 * 10 + (buff1.get_number()[i] - 48);
    }
    for (int i = 0; i < buff2.get_number().length(); i++) {
        num2 = num2 * 10 + (buff2.get_number()[i] - 48);
    }
    num1 += num2;
    return std::to_string(num1);
}

LongInt operator-(const LongInt& buff1, const LongInt& buff2) {
    int num1 = 0;
    int num2 = 0;
    for (int i = 0; i < buff1.get_number().length(); i++) {
        num1 = num1 * 10 + (buff1.get_number()[i] - 48);
    }
    for (int i = 0; i < buff2.get_number().length(); i++) {
        num2 = num2 * 10 + (buff2.get_number()[i] - 48);
    }
    num1 -= num2;
    return std::to_string(num1);
}

LongInt operator*(const LongInt& buff1, const LongInt& buff2) {
    int num1 = 0;
    int num2 = 0;
    for (int i = 0; i < buff1.get_number().length(); i++) {
        num1 = num1 * 10 + (buff1.get_number()[i] - 48);
    }
    for (int i = 0; i < buff2.get_number().length(); i++) {
        num2 = num2 * 10 + (buff2.get_number()[i] - 48);
    }
    num1 *= num2;
    return std::to_string(num1);
}

LongInt operator/(const LongInt& buff1, const LongInt& buff2) {
    int num1 = 0;
    int num2 = 0;
    for (int i = 0; i < buff1.get_number().length(); i++) {
        num1 = num1 * 10 + (buff1.get_number()[i] - 48);
    }
    for (int i = 0; i < buff2.get_number().length(); i++) {
        num2 = num2 * 10 + (buff2.get_number()[i] - 48);
    }
    num1 /= num2;
    return std::to_string(num1);
}

void LongInt::set_number(const std::string set) {
    this->number = set;
}

int main() {
    int m = 0;
    std::vector<LongInt> vec;
    while (m != 0) {
        printf("Меню:");
        printf("0.Выход.");
        printf("1.Добавить элемент.");
        printf("2.Вывод.");
        printf("3.Сложение 2-х последних чисел.");
        scanf("%i", m);
        if (m == 1) {
            std::string str1;
            printf("Введите элемент: ");
            scanf("%s", str1);
            vec.push_back(str1);
            printf("Добавлено.");
            printf("");
            printf("");
        }
        else if (m == 2) {
            for (int i = 0; i < vec.size(); i++) {
                vec[i].print();
            }
        }
        else if (m == 3) {
            LongInt sum;
            sum = vec[vec.size()] + vec[vec.size() - 1];
            printf("%s", sum);
        }
    }
    exit(0);
    return 0;
}