Research on recognition strategy based on six kinds basic word of C program

Having converting the C character sequence into word sequence, this paper puts forwarded that C program contains six kinds of basic word: identifier, keyword, constant, operator, separator and comment. The way of the open word recognition by lexical rules and closed word by comparison of one word is first applied in this paper to put forward the identification strategy about the main features of six kinds of basic word and recognition technology of each type of word in the C program, which provides the basis for the automatic scoring system of C program.