# Write a program that outputs all possibilities to put + or - or nothing between the numbers 1, 2, ..., 9 (in this order) # such that the result is always 100. For example: 1 + 2 + 34 – 5 + 67 – 8 + 9 = 100.

gistfile1.rb

['+', '-', ''].repeated_permutation(8).each do |perm|
  sumText = ('1'..'8').zip(perm).flatten.join + '9'
  sum = eval(sumText)
  if sum == 100
    puts "#{sumText} = 100"
  end
end