Question

Possible Duplicate:
count duplicate elements in ruby array

I just started learning ruby and I wish to achieve something like this.
Let say I have an array

["student", "student", "teacher", "teacher", "teacher"]

What I’m trying to do is to count the number of student and teacher and store it into a hash, so that i can get

{:student= > 2, :teacher=> 3}

Could someone give me some kind of direction on how to do this?

Answer 1

You should check this answer, which gives this example:

# sample array
a=["aa","bb","cc","bb","bb","cc"]

# make the hash default to 0 so that += will work correctly
b = Hash.new(0)

# iterate over the array, counting duplicate entries
a.each do |v|
  b[v] += 1
end

b.each do |k, v|
  puts "#{k} appears #{v} times"
end