static std::vector<std::variant<long,char>> getChars(TokenType t){
            std::vector<std::variant<long,char>> ret;
            switch (t) {
                case TokenType::BINOP:
                    ret = {'+','-','*','/'};
                    break;
                case TokenType::NUMBER:
                    ret = {1,2,3,4,5,6,7,8,9,0};
                    break;
                case TokenType::LP:
                    ret = {'('};
                    break;
                case TokenType::RP:
                    ret = {')'};
                    break;
                default:
                    ret = {};
            }
            return ret;
        }