eight.rb

@stack = []
@stack.push 3
@stack.push 5
@stack.push(@stack.pop + @stack.pop)
puts @stack.pop

eight.sc

3 5 add printi

simple_cambridge.rb

require 'pp'
program = $stdin.read
puts "@stack = []"
split_prog = program.split

split_prog.each do |thing|
  case thing
  when /^\d+$/
    puts "@stack.push #{thing.to_i}"
  when 'add'
    puts "@stack.push(@stack.pop + @stack.pop)"
  when 'mult'
    puts "@stack.push(@stack.pop * @stack.pop)"
  when 'printi'
    puts "puts @stack.pop"
  end
end