def sol1_create
          @reponse = Reponse.new(params[:reponse])
          @reponse.id_videos = "1"
          @reponse.id_candidats = session[:candidat]
          @reponse.save

          @expert = Reponse.find(:all,:conditions => ['id_candidats = :id_candidats and id_videos = :id_videos',  { :id_candidats => '1' , :id_videos => '1' }] )
          @expert.each { |l| @res_exec = l.execution}
          @diff = @res_exec - @reponse.execution
          @reponse.res_exec = @diff
          breakpoint
          flash[:notice] = 'Reponse was successfully created.'
          redirect_to :action => 'sol2'
end


irb(#<UserController:0xa79596f4>):003:0* @diff
=> 0.8
irb(#<UserController:0xa79596f4>):004:0> @reponse.res_exec
=> 0