text: #include "../src/expr.hpp"
  #include <iostream>
  #include <string>
  
  int main()
  {
  	std::string s;
  	while (std::getline(std::cin, s))
  	{
  		try
  		{
  			std::cout << *expr::parse_expr(s) << std::endl;
  		}
  		catch (const char *s)
  		{
  			std::cerr << "ERROR: " << s << std::endl;
  		}
  	}
  }
  