benchmark/so_fannkuch.yml


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prelude: |
  # The Computer Language Shootout
  # http://shootout.alioth.debian.org/
  # Contributed by Sokolov Yura
  # Modified by Ryan Williams
benchmark:
  so_fannkuch: |

    def fannkuch(n)
       maxFlips, m, r, check = 0, n-1, n, 0
       count = (1..n).to_a
       perm = (1..n).to_a

       while true
          if check < 30
             puts "#{perm}"
             check += 1
          end

          while r != 1
             count[r-1] = r
             r -= 1
          end

          if perm[0] != 1 and perm[m] != n
             perml = perm.clone #.dup
             flips = 0
             while (k = perml.first ) != 1
                perml = perml.slice!(0, k).reverse + perml
                flips += 1
             end
             maxFlips = flips if flips > maxFlips
          end
          while true
             if r==n then return maxFlips end
             perm.insert r,perm.shift
             break if (count[r] -= 1) > 0
             r += 1
          end
       end
    end

    def puts *args
    end

    N = 9 # (ARGV[0] || 1).to_i
    puts "Pfannkuchen(#{N}) = #{fannkuch(N)}"
loop_count: 1