Code to introduce even number of participants to each other every other week

catch_up.rb

people = %w[John Mary Bob Peter Susan Paula]

# Works only for even number of participants
if people.size % 2 == 0
  half_index = (people.size / 2) - 1
  first_person = people.shift
  rotating_people = people[0...half_index] + people[half_index..].reverse
  (0..people.size - 1).each do |i|
    first_half = [first_person, *rotating_people[0...half_index]]
    second_half = rotating_people[half_index..].reverse
    puts "--------Week #{i + 1}---------"
    puts first_half.zip(second_half).map { |a, b| [a, b].join("<->") }
    rotating_people.rotate!(-1)
    puts ""
  end
end

# Output:
# --------Week 1---------
# John<->Peter
# Mary<->Susan
# Bob<->Paula

# --------Week 2---------
# John<->Susan
# Peter<->Paula
# Mary<->Bob

# --------Week 3---------
# John<->Paula
# Susan<->Bob
# Peter<->Mary

# --------Week 4---------
# John<->Bob
# Paula<->Mary
# Susan<->Peter

# --------Week 5---------
# John<->Mary
# Bob<->Peter
# Paula<->Susan