When we are interested in deterministic computation, it is conventional to base the definitions of the classical complexity classes defined in this section on the model \(\mathfrak{T}\).  Supposing that \(t(n)\) and \(s(n)\) are respectively time and space constructible functions, the classes \(\textbf{TIME}(t(n))\) and \(\textbf{SPACE}(s(n))\) are defined as follows: