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

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