#include
#include
#include
#include
#include
#include
using?namespace?std;
?
#define?BUFLEN?256
#define?MAXLEN?256
#define?MAXTOKENLEN?40
#define?MAXCHILDREN?4
static?int?lineno;
static?int?linepos?=?0;
static?int?EOF_FLAG?=?false;
static?int?bufsize?=?0;
static?char?lineBuf[BUFLEN];
FILE?*?source;
char?tokenString[41];
string?output;//輸出文件
?
enum?TokenType
{
	ENDFILE?ERROR
	IF?ELSE?INT?RETURN?VOID?WHILE
	ID?NUM
	EQ?ASSIGN?LT?GT?PLUS?MINUS?TIMES?OVER?LPAREN?RPAREN?SEMI?LBRACKET?RBRACKET?LBRACE?RBRACE?COMMA
	GEQ?NEQ?LEQ
};

?
enum?StateType
{
	START?INASSIGN?INCOMMENT?INNUM?INID?DONE?PRECOMMENT?AFTERCOMMENT
};
?
struct
{
	char*?str;
	TokenType?tok;
}ReserverWords[6]=?
{?{“if“IF}{“else“ELSE}{“int“INT}{“return“RETURN}{“void“VOID}{“while“WHILE}?};

void?UnGetNextChar（）?????//回退?
{
	if?（!EOF_FLAG）
		linepos--;
}
?
int?GetNextChar（）
{
	
	if（!（linepos?	{
		lineno++;
		if（fgets（lineBuf255source））
		{
			bufsize?=?strlen（lineBuf）;
			linepos?=?0;
			return?lineBuf[linepos++];
		}
		else
		{
			EOF_FLAG=true;
			return?EOF;
		}
	}
	else
	{
		return?lineBuf[linepos++];
	}
}
?
TokenType?IsReserved（char?*?s）
{
	int?i;
	for?（i?=?0;?i?	{
		if（!strcmp（sReserverWords[i].str））
		{
			return?ReserverWords[i].tok;
		}
	}
	return?ID;
}
?
TokenType?GetToken（）
{
	StateType?state?=?START;//初始狀態為start
	bool?save;
	TokenType?CurrentToken;
	int?tokenStringIndex?=?0;
	string?assign?=?““;
	while（state?!=?DONE）
	{
		int?ch?=?GetNextChar（）;
		save?=?true;???????????//判斷是否是終結狀態
		switch?（state）
		{
		case?START:
			if?（isdigit（ch））
			{
				state?=?INNUM;
			}
			else?if?（isalpha（ch））
			{
				state?=?INID;
			}
			else?if?（（ch?==?‘<‘）||（ch?==?‘>‘）||（ch?==?‘=‘）||（ch?==?‘!‘））
			{	
				state?=?INASSIGN;
				assign?+=?char（ch）;
			}
			else?if?（（ch?==?‘?‘）?||?（ch?==?‘\t‘）?||?（ch?==?‘\n‘））
				save?=?false;
			else?if?（ch?==?‘/‘）
			{
				save?=?false;
				state?=?PRECOMMENT;
			}
			else
			{
				state?=?DONE;
				switch?（ch）
				{
				case?EOF:
					save?=?false;
					CurrentToken?=?ENDFILE;
					break;
				case?‘+‘:
					CurrentToken?=?PLUS;
					break;
				case?‘-‘:
					CurrentToken?=?MINUS;
					break;
				case?‘*‘:
					CurrentToken?=?TIMES;
					break;
				case?‘（‘:
					CurrentToken?=?LPAREN;
					break;
				case?‘）‘:
					CurrentToken?=?RPAREN;
					break;
				case?‘;‘:
					CurrentToken?=?SEMI;
					break;
				case?‘[‘:
					CurrentToken?=?LBRACKET;
					break;
				case?‘]‘:
					CurrentToken?=?RBRACKET;
					break;
				case?‘{‘:
					CurrentToken?=?LBRACE;
					break;
				case?‘}‘:
					CurrentToken?=?RBRACE;
					break;
				case?‘‘:
					CurrentToken?=?COMMA;
					break;
				default:
					CurrentToken?=?ERROR;
					break;
				}
			}
		????break;
		case?INASSIGN:
			if?（ch?==?‘