Remove last element

gistfile1.rb

h = {a: 1, b: 2, c:3}
# => {:a=>1, :b=>2, :c=>3} 
a = h.flatten
# => [:a, 1, :b, 2, :c, 3] 
a.reverse!
# => [3, :c, 2, :b, 1, :a] 
a.shift(2)
# => [3, :c] 
a
# => [2, :b, 1, :a] 
new_h = Hash[*a.reverse]
# => {:a=>1, :b=>2} 
h
# => {:a=>1, :b=>2, :c=>3} 
new_h
# => {:a=>1, :b=>2} 

# O en una linea :P
Hash[*h.flatten.reverse.shift(2).reverse]

one liner is b0rked