fixbug

app/controllers/exercises_controller.rb

@@ -970,7 +970,7 @@ class ExercisesController < ApplicationController
   def start_answer
     ActiveRecord::Base.transaction do
       begin
-        ex_users_current = ExerciseUser.where(user_id:@exercise_current_user_id,exercise_id:@exercise_id)   #不能用@exercise.exercise_users，因为exercise_users删除时，只是状态改变，未删除
+        ex_users_current = ExerciseUser.where(user_id:@exercise_current_user_id,exercise_id:@exercise.id)   #不能用@exercise.exercise_users，因为exercise_users删除时，只是状态改变，未删除
         @exercise_user_current = ex_users_current&.first
         if ex_users_current.exists?
           if @exercise_user_current.start_at.blank?