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

int main()
{
	std::ios_base::sync_with_stdio(false);
	std::cin.tie(NULL);

	std::string a, b;

	std::string product;
	product.reserve(std::max(a.size(), b.size()) + 1);

	std::cin >> a >> b;

	auto getDigit = [](const std::string& s, int index)
	{
		if (index < 0)
		{
			return 0;
		}
		return s[index] - '0';
	};

	int overflow = 0;
	for (int i = 0; i < a.size() || i < b.size() || overflow != 0; i++)
	{
		const int digitA = getDigit(a, (int)a.size() - 1 - i);
		const int digitB = getDigit(b, (int)b.size() - 1 - i);

		const int currentDigitAndOverflow = overflow + digitA + digitB;
		const int currentDigit = currentDigitAndOverflow % 10;

		product.push_back('0' + currentDigit);
		
		overflow = (currentDigitAndOverflow - currentDigit) / 10;
	}

	std::reverse(product.begin(), product.end());

	std::cout << product;

	return 0;
}