change logic city

app/controllers/cities_controller.rb

 class CitiesController < ApplicationController
   def index
-    @cities_vietnam = City.vietnam
-    @cities_international = City.international
+    @cities_vietnam = City.location(1)
+    @cities_international = City.location(0)
   end
 end

app/models/city.rb

@@ -3,6 +3,5 @@ class City < ApplicationRecord
   has_many :jobs, through: :city_jobs
 
   scope :top_city, -> { joins(:jobs).group(:city_id).order('count(job_id) DESC').limit(9) }
-  scope :vietnam, -> { joins(:jobs).group(:city_id).order('count(job_id) DESC').where(location: 1) }
-  scope :international, -> { joins(:jobs).group(:city_id).order('count(job_id) DESC').where(location: 0) }
+  scope :location, ->(number) { joins(:jobs).group(:city_id).order('count(job_id) DESC').where(location: number) }
 end