#include <iostream>
#include <fstream>
#include <vector>
#include <string>
#include <utility>
#include <functional>
#include <algorithm>
#include <cassert>

using namespace std;

struct long_num
{
	static constexpr int BASE = 10;

	vector<int> digits;

	explicit long_num(int x = 0) //privychka pisat' explicit
		: digits(1, x)
	{
		normalize();
	}

	long_num operator + (long_num const& other) const
	{
		long_num result;
		result.digits.assign(max(digits.size(), other.digits.size()), 0);
		for (size_t i = 0; i < digits.size(); ++i)
			result.digits[i] += digits[i];
		for (size_t i = 0; i < other.digits.size(); ++i)
			result.digits[i] += other.digits[i];

		result.normalize();
		return result;
	}

	long_num operator - (long_num const& other) const
	{
		long_num result;
		result.digits.assign(max(digits.size(), other.digits.size()), 0);
		for (size_t i = 0; i < digits.size(); ++i)
			result.digits[i] += digits[i];
		for (size_t i = 0; i < other.digits.size(); ++i)
			result.digits[i] -= other.digits[i];

		result.normalize();
		return result;
	}

	long_num operator * (long_num const& other) const
	{
		long_num result;
		result.digits.assign(digits.size() + other.digits.size(), 0);
		for (size_t i = 0; i < digits.size(); ++i)
			for (size_t j = 0; j < other.digits.size(); ++j)
				result.digits[i + j] += digits[i] * other.digits[j]; //TODO: check perepolneniya; budet rabota' do overdofiga dliny, tk BASE == 10

		result.normalize();
		return result;
	}

	void normalize()
	{
		for (size_t i = 0; i < digits.size(); ++i)
			if (!(0 <= digits[i] && digits[i] < BASE)) //kazhetsya, delit' dol'she chem ifat'
			{
				auto p = digits[i] / BASE, q = digits[i] % BASE; //digits[i] == p * BASE + q
				if (q < 0)
					p -= 1, q += BASE; //p * BASE + q == (p - 1) * BASE + (q + BASE)

				assert(p != 0); //perenos est' vsegda

				if (i + 1 == digits.size()) //mesto est'? a esli naidu?
				{
					if (p == -1 && q == BASE - 1)
						break;

					digits.push_back(0);
				}

				digits[i + 1] += p;
				digits[i] = q;
			}

		while (digits.size() > 1 && digits.back() == 0) //zapis' dlya 0 budet { 0 }
			digits.pop_back();
	}

	bool is_negative() const
	{
		return digits.back() < 0;
	}
};

auto read_long_num = [] (auto & stream) {
	string s;
	stream >> s;

	assert(!s.empty()); //shito eto bylo?

	bool negative = false;
	if (s[0] == '-')
	{
		negative = true;
		s.erase(s.begin());
	}

	long_num result;
	result.digits.assign(s.length(), 0);
	for (size_t i = 0; i < s.length(); ++i)
		result.digits[s.length() - i - 1] = s[i] - '0';

	static_assert(long_num::BASE == 10, "zdes' dolzhen byt' perevod");

	result.normalize();

	if (negative)  //a chto eshe takoe unarnyj minus?
		result = long_num(0) - result;

	return result;
};

auto write_long_num = [] (auto & stream, long_num value) { //kopiruem special'no
	static_assert(long_num::BASE == 10, "zdes' dolzhen byt' perevod");

	if (value.is_negative())
	{
		stream << '-';
		value = long_num(0) - value;
	}

	for (size_t i = 0; i < value.digits.size(); ++i)
		stream << char('0' + value.digits[value.digits.size() - i - 1]);
};

int main()
{
	ifstream cin("input.txt");
	ofstream cout("output.txt");

	long_num a = read_long_num(cin);
	long_num b = read_long_num(cin);
	write_long_num(cout, a - b);
}