test.rb

test.rb

def hr
  puts
  puts '-' * 80
  puts
end

# Number comparsion
def number_comparison(a, b)
  difference = a - b
  puts "#{a} is #{difference} larger than #{b}"
end

number_comparison(5, 1)
number_comparison(21, 5)
hr

# Array sum
def array_sum(array)
  sum = 0
  array.each { |nr| sum = sum + nr}
  puts sum
  # also: array.inject(:+)
end

array_sum([1, 2])
array_sum([5, 1, 0])
hr

# Array with steps
# 5 Min
# 
def array_with_steps(step_size, array_length)
  out = []
  last = 0
  array_length.times do
    out << (last + step_size)
    last = out.last
  end
  out
end

p array_with_steps(1, 3)
p array_with_steps(1, 5)
p array_with_steps(3, 4)
hr


# also
def array_with_steps(step_size, array_length)
  Array.new(array_length) { |i| (i + 1) * step_size }
end

p array_with_steps(1, 3)
p array_with_steps(1, 5)
p array_with_steps(3, 4)
hr

# Ordinal  ordinal(1) outputs the string "1st"
# 5
def ordinal(nr)
  suffix = if (nr == 1 || nr == 21)
    "st"
  elsif (nr == 2 || nr == 22)
    "nd"
  elsif (nr == 3 || nr == 23)
    "rd"
  else
    "th"
  end
  "#{nr}#{suffix}"
end

(1..25).each { |nr| puts ordinal(nr) }
hr

def expenses(e1, e2)
  sum_felix   = e1.inject(:+)
  sum_stefan  = e2.inject(:+)
  if (sum_stefan > sum_felix)
    puts "Felix owes Stefan #{(sum_stefan - sum_felix) / 2} Euros"
  else
    puts "Stefan owes Felix #{(sum_felix - sum_stefan) / 2} Euros"
  end
end

felix  = [210, 22, 45]
stefan = [120, 50, 87]
expenses(felix, stefan)
hr