#include
#include?
#include?
#include?

#define?MAXRESERVED?6?//關鍵字最大程度?
#define?MAXTOKENLEN?40?//標識符最大長度?
#define?BUFLEN?256
#define?TRUE?1
#define?FALSE?0
static?char?lineBuf[BUFLEN];?/*讀取一行字符保存?*/
static?int?linepos?=?0;?/*?指示緩存中第幾個字符?*/
static?int?bufsize?=?0;?/*?當前緩存中字符串長度?*/
static?int?EOF_flag?=?FALSE;?/*?錯誤標識?*/

/*?allocate?global?variables?*/
int?lineno?=?0;
FILE?*?source;?//讀入文件?
FILE?*?listing;?//output?file?
//FILE?*?code;
/*?allocate?and?set?tracing?flags?*/
int?EchoSource?=?TRUE;
int?TraceScan?=?TRUE;
int?TraceParse?=?TRUE;
int?TraceAnalyze?=?FALSE;
int?TraceCode?=?FALSE;
int?Error?=?FALSE;


static?void?syntaxError（char?*?message）?
{??
?fprintf（listing“\n>>>?“）;?
?fprintf（listing“Syntax?error?at?line?%d:?%s“linenomessage）;?
??Error?=?TRUE;?
}?
typedef?enum?//枚舉類型，保存詞素類型
????/*?book-keeping?tokens?*/
???{ENDFILEERROR
????/*?reserved?words?*/
????IFELSEINTRETURNVOIDWHILE
????/*?multicharacter?tokens?*/
????IDNUM
????/*?special?symbols?*/
????LBRKRBRKLBRACERBRACEGTELTENEQEQASSIGNLTGTPLUSMINUSTIMESOVERLPARENRPARENSEMICOMMA
???}?TokenType;
static?TokenType?token;?/*?holds?current?token?*/
static?struct?//關鍵字字結構，方便查詢?
????{?char*?str;
??????TokenType?tok;
????}?reservedWords[MAXRESERVED]
???=?{{“if“IF}{“int“INT}{“else“ELSE}{“return“RETURN}
??????{“void“VOID}{“while“WHILE}};
typedef?enum?//枚舉類型，保存狀態
???{?STARTINRCOMINLCOMINCOMMENTINNUMINIDDONEINLTEINGTEINEEQINNEQ}
???StateType;
char?tokenString[MAXTOKENLEN+1];?//保存標識符

//節點類型?
typedef?enum?{IntK?IdK?VoidK?ConstK?Var_DeclK?Arry_DeclK?FunK?ParamsK??
ParamK?CompK?Selection_StmtK?Iteration_StmtK?Return_StmtK?AssignK?OpK??
Arry_ElemK?CallK?ArgsK?UnkownK}?NodeKind;?
//表達式類型?
typedef?enum?{VoidInteger}?ExpType;?

???
//const?int?max_child?=?4;?
//treeNode定義?包括子節點、兄弟節點、所處行號、節點類型、屬性、表達式返回類型?
typedef?struct?treeNode?
{?
	struct?treeNode?*??child[4];?
	struct?treeNode?*??sibling;?
	int?lineno;?
	NodeKind?nodekind;?
	//union?{StmtKind?stmtExpT?};?
	union?{?TokenType?op;?int?val;?const?char?*?name;}?attr;?
	ExpType?type;?
}?TreeNode;?
TreeNode?*?parse（void）;?
TreeNode?*?declaration_list（void）;?
TreeNode?*?declaration（void）;?
TreeNode?*?params（void）;?
TreeNode?*?param_list（TreeNode?*?k）;?
TreeNode?*?param（TreeNode?*?k）;?
TreeNode?*?compound_stmt（void）;?
TreeNode?*?local_declaration（void）;?
TreeNode?*?statement_list（void）;?
TreeNode?*?statement（void）;??
TreeNode?*?expression_stmt（void）;?
TreeNode?*?selection_stmt（void）;?
TreeNode?*?iteration_stmt（void）;?
TreeNode?*?return_stmt（void）;?
TreeNode?*?expression（void）;?
TreeNode?*?var（void）;?
TreeNode?*?simple_expression（TreeNode?*?k）;?
TreeNode?*?additive_expression（TreeNode?*?k）;?
TreeNode?*?term（TreeNode?*?k）;?
TreeNode?*?factor（TreeNode?*?k）;??
TreeNode?*?call（TreeNode?*?k）;?
TreeNode?*?args（void）;?

static?int?getNextChar（void）//獲取緩存中下一個字符
{?if?