c语言词法分析器（C language lexical analyzer）.docVIP

c语言词法分析器（C language lexical analyzer） C language lexical analyzer code #include iostream #include vector #include utility #include string #include fstream #include algorithm #include cstdlib Using namespace std; / / used to store the target file name String file_name; / / extract the text information in the file. String, GetText (); / / get a word, from the position to start the search I. / / and has a reference parameter J is used to return the word the last character in the str position. String GetWord (string, STR, int, I, int, J); / / this function is used to remove spaces and line breaks in continuous string / / the first parameter is a string, the second parameter is the start position / / return value is the first character of continuous spaces and line breaks after the position in the string Int DeleteNull (string, STR, int, I); I refers to the current / judge whether the character as a delimiter, it returns true and false. Bool IsBoundary (string, STR, int, I); I refers to the current / judge whether a character is an operator, it returns true and false Bool IsOperation (string, STR, int, I); / / this function will a pair array output to a file Void OutFile (vectorpairint, string V); / / this function accepts a string array, lexical analysis to it, returns an array of type pair Vectorpairint, string Analyst (vectorstring, VEC); / / the parameter transfer function to determine whether the key is it returns true and false otherwise. Bool IsKey (string str); Int, main () { Cout ###########################\n; Cout ###copyright: Giftedbird###\n; Cout ###########################\n; String com1=; String com2= \n; String, fileline=GetText (); Int, begin=0, end=0; Vectorstring array; Do { Begin=DeleteNull (fileline, begin); String nowString; NowString=GetWord (fileline, begin, end); If (end==-1) Break; If (nowSpare (COM1) nowSpare (com2)) Array.push_back (nowString); Begin=end+1; }while (true); Vectorpairint, string mid_result; Mid_result=analyst (array); OutFile