succ.rb

require 'benchmark'

Benchmark.bm do |x|
  num = 100000000

  x.report do 
    a = 0
    num.times{ a += 1 }
  end

  x.report do 
    a = 0
    num.times{ a = a + 1 }
  end

  x.report do 
    a = 0
    num.times{ a = a.succ }
  end

  x.report do
    a = 0
    num.times{ a = a.next }
  end
end

next遅かった