1.l

打开2.tab.c编译运行

%{
#include<stdio.h>
#include<string.h>
#include<stdlib.h>
#include"define.h"
%}

Letter [A-Za-z]
Digit [0-9]
D [1-9]
LetterDigit [A-Za-z0-9]
SPACE [\n\t\f\040]

%%
"+"						{return ADD;}
"-"						{return MINUS;}
"*"						{return MULTIPLY;}
"/"						{return DIVIDE;}
"="					{return EQUAL;}
"#"						{return UNEQUAL;}
"<"						{return LESS;}
"<="					{return LESSEQUAL;}
">"						{return MORE;}
">="					{return MOREEQUAL;}
":="						{return EVALUATE;}
"("						{return LPARENTHESES;}   
")"						{return RPARENTHESES;}	
","						{return COMMA;}
";"						{return SEMICOLON;}
"."						{return DOT;}
"if"					{return IF;}
"IF"					{return IF;}
"then"					{return THEN;}
"THEN"					{return THEN;}
"while"					{return WHILE;}
"WHILE"					{return WHILE;}
"do"					{return DO;}
"DO"					{return DO;}
"read"					{return READ;}
"READ"					{return READ;}
"write"					{return WRITE;}
"WRITE"					{return WRITE;}
"call"					{return CALL;}
"CALL"					{return CALL;}
"begin"					{return	BEGI;}
"BEGIN"					{return	BEGI;}
"end"					{return END;}
"END"					{return END;}
"const"					{return CONST;}
"CONST"					{return CONST;}
"var"					{return VAR;}
"VAR"					{return VAR;}
"procedure"				{return PROCEDURE;}
"PROCEDURE"				{return PROCEDURE;}
"odd"					{return ODD;}
"ODD"					{return ODD;}
{D}{Digit}*|"0"  		{return NOSIGNINTEGER;}
{Letter}{LetterDigit}*  {return IDENT;}
{Digit}{LetterDigit}*   {return ERROR;}
{SPACE}*            {}
.                       {return ERRORCHAR;}
%%

int yywrap()
{
	return 1;
}