bug修复

src/main/java/com/project/exam/domain/service/impl/AssemblePaperDomainServiceImpl.java

@@ -304,7 +304,9 @@ public class AssemblePaperDomainServiceImpl implements AssemblePaperDomainServic
                 }
                 // todo
                 candidateIds.removeIf(id -> result.stream().anyMatch(r -> r.getId().equals(id)));
-
+                if (CollUtil.isEmpty(candidateIds)){
+                    continue;
+                }
 
                 QuestionDTO bestQuestionDTO = questionMapper.selectBatchIds(candidateIds).stream()
                         .max(Comparator.comparingInt(q -> {
@@ -330,3 +332,5 @@ public class AssemblePaperDomainServiceImpl implements AssemblePaperDomainServic
         }
     }
 }
+
+