填空题的正确率问题

app/helpers/exercises_helper.rb

@@ -180,17 +180,19 @@ module ExercisesHelper
       elsif ex.question_type == Exercise::COMPLETION  #填空题
         ex_ordered = ex.is_ordered
         null_standard_answer = ex.exercise_standard_answers
-        null_stand_choice = null_standard_answer.pluck(:exercise_choice_id)  #一个exercise_choice_id可能对应多个answer_text
+        null_stand_choice = null_standard_answer.pluck(:exercise_choice_id).uniq  #一个exercise_choice_id可能对应多个answer_text
         null_stand_text = null_standard_answer.pluck(:answer_text)
         standard_answer_count = 0
         each_null_score = null_stand_choice.size > 0 ? (ex&.question_score.to_f / null_stand_choice.uniq.size).round(3) : 0.0
         all_user_count = 0
         null_stand_choice.each_with_index do |s,index|
           user_count = 0
-          s_choice_text = null_stand_text[index]
           if ex_ordered   #有序排列
+            s_choice_text = null_stand_text[index]
             user_count = user_count + effictive_users.select{|answer| answer.exercise_choice_id == s && answer.answer_text == s_choice_text}.size
           else
+            null_stand_text = null_stand_text.uniq
+            s_choice_text = null_stand_text[index]
             user_count = user_count + effictive_users.select{|answer| answer.answer_text == s_choice_text }.size  #回答了标准答案的用户
           end
 
@@ -211,7 +213,7 @@ module ExercisesHelper
 
         # percent = commit_user_ids > 0 ? (all_user_count / commit_user_ids.to_f).round(3)*100 : 0.0
 
-        user_wrong_count = (effictive_users_count - all_user_count )
+        user_wrong_count = (effictive_users_count - all_user_count)
 
         if effictive_users_count > 0 && user_wrong_count >= 0
           wrong_percent =  (user_wrong_count / effictive_users_count.to_f ).round(3)