Abstract: The programs having errors in syntax submitted to some programming examination automatic grading systems can only be given zero point.To solve this problem，which is not coincided with the habit of artificial test paper marking，an automatic grading method called key point matching is provided to tolerate syntactic errors.This method divides the student programs into basic sentence pieces and transforms every basic sentence piece or each key sentence marked in template programs to a syntax tree to do a local syntax analysis for the following key point matching.This paper focuses on the accurate expressions of specific basic syntactic and semantic points in student programs and enhances the performance of the grading system to be in accord with the idea of manual grading better.

Key words: automatic grading of programs, key point matching, local syntax analysis, basic sentence piece, syntax tree

摘要： 针对传统的编程题自动评分方法对存在个别语法错误的学生考试程序只能给出零分、不符合卷面笔试时教师手工阅卷习惯的问题，提出了一种适用于有错误的编程题的评分方法，首先，将有语法错误的学生程序分解为基本语句单元，与模板采分点语句一并经过局部语法分析，转化为语法分析树的中间表示，然后进行采分点匹配，进而输出有语法错误的学生程序的评分结果，该方法适用于考察答题者对基本语法知识的正确使用和对题目关键语义的正确表达，使得对有语法错误的学生程序的评分结果更加符合人工阅卷的思想。

关键词: 编程题自动评分, 采分点匹配, 局部语法分析, 基本语句单元, 语法分析树