update

mec-biz/src/main/java/com/ym/mec/biz/service/impl/ClassGroupServiceImpl.java

@@ -1286,7 +1286,7 @@ public class ClassGroupServiceImpl extends BaseServiceImpl<Integer, ClassGroup>
             throw new BizException("班级不存在");
         }
         Integer num = classGroupStudentMapperDao.countClassGroupStudentNum(classGroupId);
-        classGroup.setStudentNum(num - 1);
+        classGroup.setStudentNum(num);
         classGroup.setUpdateTime(new Date());
 
         classGroupDao.update(classGroup);