---
ch-1:
  - function: friday13th
    arguments: 2023
    result: 2
ch-2:
  - function: roman2int
    arguments: I
    result: 1
  - arguments: II
    result: 2
  - arguments: IV
    result: 4
  - arguments: IX
    result: 9
  - arguments: XXX
    result: 30
  - arguments: MDCLXVI
    result: 1666
  - function: int2roman
    arguments: 1
    result: I
  - arguments: 2
    result: II
  - arguments: 4
    result: IV
  - arguments: 9
    result: IX
  - arguments: 30
    result: XXX
  - arguments: 1666
    result: MDCLXVI
  - function: romanmaths
    arguments: IV + V
    result: IX
  - arguments: M - I
    result: CMXCIX
  - arguments: X / II
    result: V
  - arguments: XI * VI
    result: LXVI
  - arguments: VII ** III
    result: CCCXLIII
  - arguments: V - V
    result: nulla
  - arguments: V / II
    result: non potest
  - arguments: MMM + M
    result: non potest
  - arguments: V - X
    result: non potest