---
ch-1:
  - function: missingnumber
    arguments:
      - 0
      - 1
      - 3
    result: 2
  - function: missingnumber
    arguments:
      - 0
      - 1
    result: 2
ch-2:
  - function: pennypiles
    arguments: 5
    result: 7
  - function: pennypiles
    arguments: 10
    result: 42