# T.2. Tasks with Operators, Exceptions and OOP

The programming tasks for this block are as follows:

 1. ‹machine.*› – a simple register machine simulator [6pt],
 2. ‹natural.*› – arbitrary-size natural numbers [9pt],
 3. ‹parser.*› – parsing simplified XML [9pt],
 4. ‹complex.*› – arbitrary-precision complex numbers [12pt].

The first task only relies on knowledge from the first block and you
should be able to start working on it immediately.

Tasks 2 and 4 additionally require operator overloading (chapter 5)
and basic understanding of exceptions (chapter 6).

Finally, task 3 needs ‹unique_ptr› (chapter 7) and virtual dispatch
(chapter 8), but the parser itself (and hence ‹xml_validate›) can be
implemented with knowledge from block 1 alone. The verity tests for
‹xml_validate› will run even if the sanity for ‹xml_parse› and/or
‹xml_print› fails, so that you can start working on the parser
immediately.