#include "parser.h"
#include "expression.h"
#include "safe_int.h"
#include <iostream>
#include <iterator>
#include <boost/shared_ptr.hpp>

using namespace std;

int main()
{
	Parser* parser = Parser::get_parser();
	istream_iterator<string> in(cin);
	try
	{
		ExpressionPtr root = parser->parse(in);
		cout << root->eval() << endl;
	}
	catch (const Parser::BadInput& e)
	{
		cout << e.get_message() << endl;
		return 1;
	}
	catch (const safe_int::divide_by_zero& e)
	{
		cout << "Divide by zero" << endl;
		return 1;
	}
	catch (const safe_int::overflow& e)
	{
		cout << "Overflow" << endl;
		return 1;
	}
	catch (const safe_int::underflow& e)
	{
		cout << "Underflow" << endl;
		return 1;
	}
	
	return 0;
}