diff --git a/app/controllers/main_controller.rb b/app/controllers/main_controller.rb
--- a/app/controllers/main_controller.rb
+++ b/app/controllers/main_controller.rb
@@ -8,7 +8,7 @@
   # COMMENTED OUT: filter in each action instead
   # before_filter :verify_time_limit, :only => [:submit]
 
-  verify :method => :post, :only => [:submit, :new_input, :download_input, :submit_solution],
+  verify :method => :post, :only => [:submit, :download_input, :submit_solution],
          :redirect_to => { :action => :index }
 
   # COMMENT OUT: only need when having high load
@@ -176,8 +176,10 @@
            :locals => {:announcement_effect => true})
   end
 
+  #
   # actions for Code Jom
-  def new_input
+  #
+  def download_input
     problem = Problem.find(params[:id])
     user = User.find(session[:user_id])
     if user.can_request_new_test_pair_for? problem
@@ -187,23 +189,11 @@
       send_data(assignment.test_pair.input,
                 { :filename => "#{problem.name}-#{assignment.request_number}.in",
                   :type => 'text/plain' })
-    else 
-      flash[:notice] = 'You cannot request new input now.'
-      redirect_to :action => 'list'
-    end
-  end
-
-  def download_input
-    problem = Problem.find(params[:id])
-    user = User.find(session[:user_id])
-    recent_assignment = user.get_recent_test_pair_assignment_for problem
-    if recent_assignment != nil
+    else
+      recent_assignment = user.get_recent_test_pair_assignment_for problem
       send_data(recent_assignment.test_pair.input,
                 { :filename => "#{problem.name}-#{recent_assignment.request_number}.in",
                   :type => 'text/plain' })
-    else
-      flash[:notice] = 'You have not requested for any input data for this problem.'
-      redirect_to :action => 'list'
     end
   end
   
@@ -211,32 +201,52 @@
     problem = Problem.find(params[:id])
     user = User.find(session[:user_id])
     recent_assignment = user.get_recent_test_pair_assignment_for problem
-    if recent_assignment != nil
-      submitted_solution = params[:file].read
-      test_pair = recent_assignment.test_pair
-      passed = test_pair.grade(submitted_solution)
-      points = passed ? 100 : 0
-      submission = Submission.new(:user => user,
-                                  :problem => problem,
-                                  :source => params[:file].read,
-                                  :source_filename => params['file'].original_filename,
-                                  :language_id => 0,
-                                  :submitted_at => Time.new.gmtime,
-                                  :graded_at => Time.new.gmtime,
-                                  :points => points)
-      submission.save
-      recent_assignment.submitted = true
-      recent_assignment.save
-      if passed
-        flash[:notice] = 'Correct solution'
-      else
-        flash[:notice] = 'Incorrect solution'
-      end
-      redirect_to :action => 'list'
+    if recent_assignment == nil
+      flash[:notice] = 'You have not requested for any input data for this problem.  Please download an input first.'
+      redirect_to :action => 'list' and return
+    end
+
+    if recent_assignment.submitted
+      flash[:notice] = 'You have already submitted an incorrect solution for this input.  Please download a new input data.'
+      redirect_to :action => 'list' and return
+    end
+
+    if params[:file] == nil
+      flash[:notice] = 'You have not submitted any output.'
+      redirect_to :action => 'list' and return
+    end
+
+    submitted_solution = params[:file].read
+    test_pair = recent_assignment.test_pair
+    passed = test_pair.grade(submitted_solution)
+    points = passed ? 100 : 0
+    submission = Submission.new(:user => user,
+                                :problem => problem,
+                                :source => submitted_solution,
+                                :source_filename => params['file'].original_filename,
+                                :language_id => 0,
+                                :submitted_at => Time.new.gmtime,
+                                :graded_at => Time.new.gmtime,
+                                :points => points)
+    submission.save
+    recent_assignment.submitted = true
+    recent_assignment.save
+
+    status = user.get_submission_status_for(problem)
+    if status == nil
+      status = SubmissionStatus.new :user => user, :problem => problem, :submission_count => 0
+    end
+
+    status.submission_count += 1
+    status.passed = passed
+    status.save
+    
+    if passed
+      flash[:notice] = 'Correct solution.'
     else
-      flash[:notice] = 'You have not requested for any input data for this problem.'
-      redirect_to :action => 'list'
+      flash[:notice] = 'Incorrect solution.'
     end
+    redirect_to :action => 'list'
   end
 
   protected
@@ -254,15 +264,27 @@
   end
 
   def prepare_list_information
-    @problems = Problem.find_available_problems
+    @user = User.find(session[:user_id])
+
+    all_problems = Problem.find_available_problems
+
+    passed = {}
+    sub_count = {}
+    @user.submission_statuses.each do |status|
+      if status.passed
+        passed[status.problem_id] = true
+      end
+      sub_count[status.problem_id] = status.submission_count
+    end
+
+    @problems = all_problems.reject { |problem| passed.has_key? problem.id }
+
     @prob_submissions = Array.new
-    @user = User.find(session[:user_id])
     @problems.each do |p|
-      sub = Submission.find_last_by_user_and_problem(@user.id,p.id)
-      if sub!=nil
-        @prob_submissions << { :count => sub.number, :submission => sub }
+      if sub_count.has_key? p.id
+        @prob_submissions << { :count => sub_count[p.id] }
       else
-        @prob_submissions << { :count => 0, :submission => nil }
+        @prob_submissions << { :count => 0 }
       end
     end
     prepare_announcements
diff --git a/app/models/submission.rb b/app/models/submission.rb
--- a/app/models/submission.rb
+++ b/app/models/submission.rb
@@ -11,7 +11,7 @@
   validates_length_of :source, :maximum => 100_000, :allow_blank => true, :message => 'too long'
   validates_length_of :source, :minimum => 1, :allow_blank => true, :message => 'too short'
   validate :must_have_valid_problem
-  validate :must_specify_language
+  #validate :must_specify_language
 
   before_save :assign_latest_number_if_new_recond
 
diff --git a/app/models/submission_status.rb b/app/models/submission_status.rb
new file mode 100644
--- /dev/null
+++ b/app/models/submission_status.rb
@@ -0,0 +1,6 @@
+class SubmissionStatus < ActiveRecord::Base
+
+  belongs_to :user
+  belongs_to :problem
+
+end
diff --git a/app/models/user.rb b/app/models/user.rb
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -17,6 +17,7 @@
            :order => 'created_at DESC'
 
   has_many :test_pair_assignments, :dependent => :delete_all
+  has_many :submission_statuses
 
   belongs_to :site
   belongs_to :country
@@ -111,6 +112,14 @@
     end
   end
 
+  def get_submission_status_for(problem)
+    SubmissionStatus.find(:first,
+                          :conditions => {
+                            :user_id => id,
+                            :problem_id => problem.id
+                          })
+  end
+
   def email_for_editing
     if self.email==nil
       "(unknown)"
diff --git a/app/views/main/_problem.html.erb b/app/views/main/_problem.html.erb
deleted file mode 100644
--- a/app/views/main/_problem.html.erb
+++ /dev/null
@@ -1,26 +0,0 @@
-<div id="problem-panel-<%= problem.id %>" class="problem-panel" style="display:none">
-  <div id="problem-form-<%= problem.id %>" class="problem-form">
-    <% form_tag({:action => 'new_input', :id => problem.id}, :method => :post) do -%>
-      <input type="submit" value="New input"/>
-    <% end -%>
-    <% form_tag({ :action => 'download_input', :id => problem.id }, :method => :post) do -%>
-      <input type="submit" value="Download input"/>
-    <% end -%>
-    <% form_tag({ :action => 'submit_solution', :id => problem.id }, :method => :post, :multipart => true) do -%>
-      <input type="file" name="file">
-      <input type="submit" value="Submit solution"/>
-    <% end -%>
-  </div>
-
-  <div class="problem-description">
-    <% if problem.description!=nil %>
-      <% if problem.description.markdowned %>
-<%= markdown(problem.description.body) %>
-      <% else %>
-<%= problem.description.body %>
-      <% end %>
-    <% else %>
-      (not available)
-    <% end %>
-  </div>
-</div>
diff --git a/app/views/main/_problem.html.haml b/app/views/main/_problem.html.haml
new file mode 100644
--- /dev/null
+++ b/app/views/main/_problem.html.haml
@@ -0,0 +1,18 @@
+.problem-panel{:id => "problem-panel-#{problem.id}", :style => "display:none"}
+  .problem-form{:id => "problem-form-#{problem.id}"}
+    - form_tag({ :action => 'download_input', :id => problem.id }, :method => :post) do
+      %b Input:
+      %input{:type => "submit", :value => "Download input"}
+    - form_tag({ :action => 'submit_solution', :id => problem.id }, :method => :post, :multipart => true) do
+      %b Submit output:
+      %input{:type => "file", :name => "file"}
+      %input{:type => "submit", :value => "Submit solution"}
+
+  .problem-description
+    - if problem.description!=nil
+      - if problem.description.markdowned
+        = markdown(problem.description.body)
+      - else
+        = problem.description.body
+    - else
+      (not available)
diff --git a/db/migrate/20100123154326_create_submission_statuses.rb b/db/migrate/20100123154326_create_submission_statuses.rb
new file mode 100644
--- /dev/null
+++ b/db/migrate/20100123154326_create_submission_statuses.rb
@@ -0,0 +1,16 @@
+class CreateSubmissionStatuses < ActiveRecord::Migration
+  def self.up
+    create_table :submission_statuses do |t|
+      t.integer :user_id
+      t.integer :problem_id
+      t.boolean :passed
+      t.integer :submission_count
+
+      t.timestamps
+    end
+  end
+
+  def self.down
+    drop_table :submission_statuses
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -9,7 +9,7 @@
 #
 # It's strongly recommended to check this file into your version control system.
 
-ActiveRecord::Schema.define(:version => 20100118174404) do
+ActiveRecord::Schema.define(:version => 20100123154326) do
 
   create_table "announcements", :force => true do |t|
     t.string   "author"
@@ -129,6 +129,15 @@
     t.string   "password"
   end
 
+  create_table "submission_statuses", :force => true do |t|
+    t.integer  "user_id"
+    t.integer  "problem_id"
+    t.boolean  "passed"
+    t.integer  "submission_count"
+    t.datetime "created_at"
+    t.datetime "updated_at"
+  end
+
   create_table "submissions", :force => true do |t|
     t.integer  "user_id"
     t.integer  "problem_id"
diff --git a/test/fixtures/submission_statuses.yml b/test/fixtures/submission_statuses.yml
new file mode 100644
--- /dev/null
+++ b/test/fixtures/submission_statuses.yml
@@ -0,0 +1,13 @@
+# Read about fixtures at http://ar.rubyonrails.org/classes/Fixtures.html
+
+one:
+  user_id: 1
+  problem_id: 1
+  passed: false
+  submission_count: 1
+
+two:
+  user_id: 1
+  problem_id: 1
+  passed: false
+  submission_count: 1
diff --git a/test/unit/submission_status_test.rb b/test/unit/submission_status_test.rb
new file mode 100644
--- /dev/null
+++ b/test/unit/submission_status_test.rb
@@ -0,0 +1,8 @@
+require 'test_helper'
+
+class SubmissionStatusTest < ActiveSupport::TestCase
+  # Replace this with your real tests.
+  test "the truth" do
+    assert true
+  end
+end