Research And Implementation Of Related Technologies In Program Judging Automatically

With the rapid expansion of computer techniques in Computer Assisted Instruction,people are more and more interested in Computer Automatic Judging Technique.The judging techniques to objective problems are almost perfect in current Judging System,but to subjective problems are also in researching stage.Although some program judging systems have been put into operation,most of these only judging the output results which have not considered the students'program from the view of program understanding and semantic analysis.The result is that the students will not get the corresponding score whit their mistake programs.Contraposing the lack of current Program Automatic Judging System,thesis designed a model which can realize the Program Automatic Judging.The paper adopt the integrate manner of automatic and static according to the students'executive programs in the model. In the process of automatic judging, this paper cited a method of code executive reliabilty function which compute the corresponding score though by the output reliabilty of the students'programs. In the process of static judging,this paper realized the judging on the program structure which from the view of program understanding,used system dependence graph as the middle represented of the program and blocked weighting to the program according to the control dependency of system dependence graph. Simultaneously,it should be standardizing processed to the program that bond with the technique of semantic similarity equivalent transformation. Similar binary syntax tree is utilized to depict the program expression,removed the diversification of expression structure though by formation rule of the similar binary syntax tree.Additionally ,in order to normalizing process the program variable ,we need to compare the expression structure.Finally, we utilized the model to the actual program automatic judging in order to experiment. The result show that this method can realize the automatic judging to the students'programs and gave a better utility value.