Use hash to count elements in an array : Array Extension « Array « Ruby






  1. Ruby
  2. Array
  3. Array Extension

Use hash to count elements in an array


class Array

  def count
    k=Hash.new(0)
    self.each{|x| k[x]+=1 }
    k
  end

end

meal = %w[spam spam eggs ham eggs spam]
items = meal.count
# items is {"ham" => 1, "spam" => 3, "eggs" => 2}
spams = items["spam"]   # 3








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