Send More Money solved with Ruby (brute-force)

send_more_money.rb

# Send More Money
#
# Verbal Arithmetic https://en.wikipedia.org/wiki/Verbal_arithmetic

letters = %i[s e n d m o r y]

check = ->(vals) do
  # leading zeros are not allowed
  return false if vals[:s] == 0 || vals[:m] == 0

  send = ("%{s}%{e}%{n}%{d}" % vals).to_i
  more = ("%{m}%{o}%{r}%{e}" % vals).to_i
  money = ("%{m}%{o}%{n}%{e}%{y}" % vals).to_i

  send + more == money
end

# this makes 10 items for 0 through 9 assignments
items = letters + [nil, nil]

items.permutation.each_with_index do |set, i|
  number_processed = i + 1

  solution = set # one permutation of letters + 2 nils
    .zip(0..9).to_h # zip into hash with positions, aka values
    .reject { |key, _| key.nil? } # throw out the nils

  case solution
  when check
    puts "" # newline
    puts "Solution Found (potential solutions processed: #{number_processed})"
    puts solution
    break
  else
    print "."
  end
end

# Solution Found (potential solutions processed: 2005114)
# {:o=>0, :m=>1, :y=>2, :e=>5, :n=>6, :d=>7, :r=>8, :s=>9}