big_number

#include <iostream>
#include <string>
#include <algorithm>

char compare(std::string s1, std::string s2)
{
    if(s1.length() != s2.length()) {
        return (s1.length() > s2.length()) ? '>' : '<';
    } else {
        while(s1.length()) {
            if(s1[0] > s2[0]) {
                return '>';
            } else if (s1[0] < s2[0]) {
                return '<';
            }
            s1.erase(0, 1);
            s2.erase(0, 1);
        }
        return '=';
    }
}

int toi(char ch) {
    return ch - '0';
}

char toc(int i) {
    return i + '0';
}

std::string op_plus(std::string s1, std::string s2) {
    std::string s_add = "";
    int tmp = 0;
    while (s1 != "" || s2 != "" || tmp != 0) {
        if (s1 != "") {
            tmp += toi(s1[s1.length()-1]);
            s1.erase(s1.length()-1);
        }
        if (s2 != "") {
            tmp += toi(s2[s2.length()-1]);
            s2.erase(s2.length()-1);
        }
        s_add += toc(tmp%10);
        tmp /= 10;
    }
    while (s_add[s_add.length()-1] == '0' && s_add.length() != 1) {
        s_add.erase(s_add.length()-1);
    }
    std::reverse(s_add.begin(), s_add.end());
    return s_add;
}

std::string op_minus(std::string s1, std::string s2) {
    std::string s_sub = "";
    int tmp = 0;
    char cmp = compare(s1, s2);
    if (cmp == '=') {
        return "0";
    } else if (cmp == '<'){
        std::swap(s1, s2);
    }
    while (s1 != "") {
        if (s2 != "") {
            tmp += toi(s1[s1.length()-1]) - toi(s2[s2.length()-1]);
            s2.erase(s2.length()-1);
        } else {
            tmp += toi(s1[s1.length()-1]);
        }
        s1.erase(s1.length()-1);
        if (tmp < 0) {
            s_sub += toc(tmp + 10);
            tmp = -1;
        } else {
            s_sub += toc(tmp);
            tmp = 0;
        }
    }
    while (s_sub[s_sub.length()-1] == '0' && s_sub.length() != 1) {
        s_sub.erase(s_sub.length()-1);
    }
    if (cmp == '<') {
        s_sub += "-";
    }
    std::reverse(s_sub.begin(), s_sub.end());
    return s_sub;
}

std::string op_time_by_one_digit(std::string s1, char s2) {
    std::string s_mul = "0";
    if (s2 == '0') {
        return "0";
    } else {
        for (int i = 0; i < (s2-'0'); ++i) {
            s_mul = op_plus(s_mul, s1);
        }
        return s_mul;
    }
}

std::string op_time(std::string s1, std::string s2) {
    std::string s_mul = "0", zero = "";
    if (compare(s1, s2) == '<') {
        std::swap(s1, s2);
    }
    while(s2 != "") {
        s_mul = op_plus(s_mul, op_time_by_one_digit(s1, s2[s2.length()-1]) + zero);
        s2.erase(s2.length()-1);
        zero += "0";
    }
    return s_mul;
}

std::string op_divide(std::string s1, std::string s2) {
    std::string s_div = "1";
    if (s1 == s2) {
        return "1";
    }

    while (compare(op_time(s_div, s2), s1) != '>') {
        s_div += "0";
    }
    s_div.erase(s_div.length()-1);

    std::string tmp = s_div;
    s_div = "0";
    for (int i = 0; i < s_div.length(); ++i) {
        for (int j = 0; j < 9; ++j) {
            if (compare(op_time(s_div, s2), s1) == '>') {
                s_div = op_minus(s_div, tmp);
                break;
            } else if (compare(op_time(s_div, s2), s1) == '=') {
                return s_div;
            }
            s_div = op_plus(s_div, tmp);
        }
        if (tmp != "") {
            tmp.erase(tmp.length()-1);
        }
    }
    return s_div;
}

int main()
{
    std::string s1, s2, ans;
    char ope;
    while (std::cin >> s1 >> ope >> s2) {
        ans = "";
        switch (ope) {
            case '+':
                ans = op_plus(s1, s2);
                break;
            case '-':
                ans = op_minus(s1, s2);
                break;
            case '*':
                ans = op_time(s1, s2);
                break;
            case '/':
                ans = op_divide(s1, s2);
                break;
            default:
                std::cerr << "Operator was not defined." << std::endl;
                return 1;
        }
        std::cout << ans << std::endl;
    }
    return 0;
}