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

Use hash to count elements in an array

class Array

  def count
    self.each{|x| k[x]+=1 }


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


Related examples in the same category

1.Add your method to system data type
2.Add a new method to Array class
3.Add shuffle method to Array class
4.strip values from array
5.Extract array in place
6.Array cartesian
7.Add method to Array class to convert an array to a hash
8.each from both sides
9.Extends array comparsion method
10.Override array method
11.Add new operator for Array
12.Add subset and superset operator for Array
13.Set permutation for Array
14.Resequence the array
15.convert array to a hash