【编译原理】扩展试验_语法制导翻译_2_B_2.将表达式翻译为后缀式-LR分析

编译原理最后的单人实验。

学校:烟大

老师是孔老师,孔老师是位十分认真负责的老师,跟着孔老师学了半年感觉学到了很多东西,感谢孔老师。

题目如上:扩展试验_语法制导翻译_2_B_2.将表达式翻译为后缀式-LR分析

 

【编译原理】扩展试验_语法制导翻译_2_B_2.将表达式翻译为后缀式-LR分析

本题扩展了乘法,括号的后缀转换,由于加法和减法,乘法和除法运算逻辑相同,所以只需实现加法,乘法,括号运算。

后面会贴上自己源码的下载链接:

词法分析部分由lex实现,语法分析手动构造的。

本实验代码参考了老师给的计算器calc.lex范例程序,和16级学长的实现方法,在此鸣谢。


源码分享:https://download.csdn.net/my/uploads 编译原理-2019压缩包正在审核。

百度云:链接:https://pan.baidu.com/s/1DZdJzZO4gCbaHyCZlxXxHw 
提取码:o2vq


lex:

%option noyywrap
%{
    #include <stdio.h>
       #include <stdlib.h>
    int num=0;
       int num_num = 0;
       int num_op = 0;
       int aa[200]={0};
       char cc[200]={0};
%}

INTEGER [1-9][0-9]*

ID [a-zA-Z][a-zA-Z]*

operate [+-*()]

SPACE [ \n\t]

over [#]

%%
{over} {
    return 0;
}
{operate} {
    cc[num]=*yytext;
    num++;
        
}

{INTEGER} { 

    aa[num_num]=atoi(yytext);
    cc[num]='i';
    num++;     
      num_num++;

    /*数字数加一*/

}


 

{SPACE} {

   /*什么也不做,滤掉白字符和其它字符*/

}
. {
    printf("error\n");
}
%%

int www()

{
    yylex();
     return 0;

}
 


LR分析部分:

LR.c文件:

#include<stdio.h>
#include<string.h>
#include"lex.h"
char *action[12][6]={"S5#",NULL,NULL,"S4#",NULL,NULL,            /*ACTION表*/
                      NULL,"S6#",NULL,NULL,NULL,"acc",
                      "R2#","R2#","S7#","R2#","R2#","R2#",
                      "R4#","R4#","R4#","R4#","R4#","R4#",
                      "S5#",NULL,NULL,"S4#",NULL,NULL,
                      "R6#","R6#","R6#","R6#","R6#","R6#",
                      "S5#",NULL,NULL,"S4#",NULL,NULL,
                      "S5#",NULL,NULL,"S4#",NULL,NULL,
                      NULL,"S6#",NULL,NULL,"S11#",NULL,
                      "R1#","R1#","S7#","R1#","R1#","R1#",
                      "R3#","R3#","R3#","R3#","R3#","R3#",
                      "R5#","R5#","R5#","R5#","R5#","R5#"};

int goto1[12][3]={1,2,3,                          /*GOTO表*/
                  0,0,0,
                  0,0,0,
                  0,8,0,
                  8,2,3,
                  0,0,0,
                  0,9,3,
                  0,0,10,
                  0,0,0,
                  0,0,0,
                  0,0,0,
                  0,0,0};

char vt[6]={'i','+','*','(',')','#'};                       /*存放非终结符*/
char vn[3]={'E','T','F'};                           /*存放终结符*/
char *LR[7]={"L-E#","E-E+T#","E-T#","T-T*F#","T-F#","F-(E)#","F-i#"};    /*存放产生式*/

int a[20];                /*状态栈*/
char b[20],c[20],c1;    /*符号栈, 剩余符号栈*/
int top1,top2,top3,top,m,n;
/*运行*/
void main(){
    int g,h,i,j,k,l,p,y,z,count,dd=0;
    char x,copy[10],copy1[10];
    int top4=0;
    char id[20];
    top1=0;            //状态栈栈顶
    top2=0;            //符号栈栈顶
    top3=0;            //指向最后一个符号串,记录输入符号的个数
    top=0;            //top指向输入栈栈顶

    a[0]=0;            //状态栈
    y=a[0];
    b[0]='#';        //符号栈
    count=0;z=0;

    printf("请输入表达式\n");
    www();
    cc[num]='#';
    do{
        y=z;            /*y,z指向状态栈栈顶*/
        m=0;
        n=0;
        g=top;                //top指向输入栈栈顶
        j=0;
        k=0;
        x=cc[top];

        while(x!=vt[j]&&j<=5) j++;            //判断当前符号是否是终结符

        if(j==5&&x!=vt[j]){
            printf("error\n");
            return;
        }

        if(action[y][j]==NULL){                /*查表*/
            printf("error\n");
            return;
        }
        else
            strcpy(copy,action[y][j]);

        if(copy[0]=='S')

        {                    /*处理移进*/
            i=1;
            h=copy[i]-'0';                            //计算下一个状态
            i++;
            while(copy[i]>='0'&&copy[i]<='9')
            {
                h=copy[i]-'0';
                i++;
            }
            i=i-1;

            z=copy[1]-'0';
            for(j=2;j<=i;j++)
            {
                z=z*10+copy[j]-'0';
            }

            top1=top1+1;
            top2=top2+1;
            a[top1]=z;                        //将下一个状态数移进状态栈
            b[top2]=x;                        //将读到的这个字符移进符号栈

            top=top+1;

        }

        if(copy[0]=='R'){                      /*处理归约*/

            h=copy[1]-'0';                    //H记录的是归约用到的产生式

            if(h==6)
            {
                printf("%d ",aa[dd]);
                dd++;
            }
            if(h==3)
            {
                printf("* ");
            }
            if(h==1)
            {
                printf("+ ");
            }

            strcpy(copy1,LR[h]);            //copy1记录当前归约用到的产生式

            while(copy1[0]!=vn[k]) k++;        //k记录归约后产生的非终结符的位置

            l=strlen(LR[h])-4;

            //top1=top1-l+1;
            //top2=top2-l+1;
            top1=top1-l;
            top2=top2-l;

            y=a[top1-1];                    //记录当前状态的上一个状态

            p=goto1[y][k];                    //下一个要跳转的状态

            a[top1]=p;
            b[top2]=copy1[0];
            z=p;

        }
    }while(action[y][j]!="acc");
    printf("\nacc\n");
    for(i=0;i<top4;i++)
        printf("%c ",id[i]);
    printf("\n");
}

lex.h文件

/* A lexical scanner generated by flex */
/*LEX头文件*/

/* Scanner skeleton version:
 * $Header: /home/daffy/u0/vern/flex/RCS/flex.skl,v 2.85 95/04/24 10:48:47 vern Exp $
 */

#define FLEX_SCANNER
#define YY_FLEX_MAJOR_VERSION 2
#define YY_FLEX_MINOR_VERSION 5

#include <stdio.h>


/* cfront 1.2 defines "c_plusplus" instead of "__cplusplus" */
#ifdef c_plusplus
#ifndef __cplusplus
#define __cplusplus
#endif
#endif


#ifdef __cplusplus

#include <stdlib.h>
#include <unistd.h>

/* Use prototypes in function declarations. */
#define YY_USE_PROTOS

/* The "const" storage-class-modifier is valid. */
#define YY_USE_CONST

#else    /* ! __cplusplus */

#if __STDC__

#define YY_USE_PROTOS
#define YY_USE_CONST

#endif    /* __STDC__ */
#endif    /* ! __cplusplus */

#ifdef __TURBOC__
 #pragma warn -rch
 #pragma warn -use
#include <io.h>
#include <stdlib.h>
#define YY_USE_CONST
#define YY_USE_PROTOS
#endif

#ifdef YY_USE_CONST
#define yyconst const
#else
#define yyconst
#endif


#ifdef YY_USE_PROTOS
#define YY_PROTO(proto) proto
#else
#define YY_PROTO(proto) ()
#endif

/* Returned upon end-of-file. */
#define YY_NULL 0

/* Promotes a possibly negative, possibly signed char to an unsigned
 * integer for use as an array index.  If the signed char is negative,
 * we want to instead treat it as an 8-bit unsigned char, hence the
 * double cast.
 */
#define YY_SC_TO_UI(c) ((unsigned int) (unsigned char) c)

/* Enter a start condition.  This macro really ought to take a parameter,
 * but we do it the disgusting crufty way forced on us by the ()-less
 * definition of BEGIN.
 */
#define BEGIN yy_start = 1 + 2 *

/* Translate the current start state into a value that can be later handed
 * to BEGIN to return to the state.  The YYSTATE alias is for lex
 * compatibility.
 */
#define YY_START ((yy_start - 1) / 2)
#define YYSTATE YY_START

/* Action number for EOF rule of a given start state. */
#define YY_STATE_EOF(state) (YY_END_OF_BUFFER + state + 1)

/* Special action meaning "start processing a new file". */
#define YY_NEW_FILE yyrestart( yyin )

#define YY_END_OF_BUFFER_CHAR 0

/* Size of default input buffer. */
#define YY_BUF_SIZE 16384

typedef struct yy_buffer_state *YY_BUFFER_STATE;

extern int yyleng;
extern FILE *yyin, *yyout;

#define EOB_ACT_CONTINUE_SCAN 0
#define EOB_ACT_END_OF_FILE 1
#define EOB_ACT_LAST_MATCH 2

/* The funky do-while in the following #define is used to turn the definition
 * int a single C statement (which needs a semi-colon terminator).  This
 * avoids problems with code like:
 *
 *     if ( condition_holds )
 *        yyless( 5 );
 *    else
 *        do_something_else();
 *
 * Prior to using the do-while the compiler would get upset at the
 * "else" because it interpreted the "if" statement as being all
 * done when it reached the ';' after the yyless() call.
 */

/* Return all but the first 'n' matched characters back to the input stream. */

#define yyless(n) \
    do \
        { \
        /* Undo effects of setting up yytext. */ \
        *yy_cp = yy_hold_char; \
        yy_c_buf_p = yy_cp = yy_bp + n - YY_MORE_ADJ; \
        YY_DO_BEFORE_ACTION; /* set up yytext again */ \
        } \
    while ( 0 )

#define unput(c) yyunput( c, yytext_ptr )

/* The following is because we cannot portably get our hands on size_t
 * (without autoconf's help, which isn't available because we want
 * flex-generated scanners to compile on their own).
 */
typedef unsigned int yy_size_t;


struct yy_buffer_state
    {
    FILE *yy_input_file;

    char *yy_ch_buf;        /* input buffer */
    char *yy_buf_pos;        /* current position in input buffer */

    /* Size of input buffer in bytes, not including room for EOB
     * characters.
     */
    yy_size_t yy_buf_size;

    /* Number of characters read into yy_ch_buf, not including EOB
     * characters.
     */
    int yy_n_chars;

    /* Whether we "own" the buffer - i.e., we know we created it,
     * and can realloc() it to grow it, and should free() it to
     * delete it.
     */
    int yy_is_our_buffer;

    /* Whether this is an "interactive" input source; if so, and
     * if we're using stdio for input, then we want to use getc()
     * instead of fread(), to make sure we stop fetching input after
     * each newline.
     */
    int yy_is_interactive;

    /* Whether we're considered to be at the beginning of a line.
     * If so, '^' rules will be active on the next match, otherwise
     * not.
     */
    int yy_at_bol;

    /* Whether to try to fill the input buffer when we reach the
     * end of it.
     */
    int yy_fill_buffer;

    int yy_buffer_status;
#define YY_BUFFER_NEW 0
#define YY_BUFFER_NORMAL 1
    /* When an EOF's been seen but there's still some text to process
     * then we mark the buffer as YY_EOF_PENDING, to indicate that we
     * shouldn't try reading from the input source any more.  We might
     * still have a bunch of tokens to match, though, because of
     * possible backing-up.
     *
     * When we actually see the EOF, we change the status to "new"
     * (via yyrestart()), so that the user can continue scanning by
     * just pointing yyin at a new input file.
     */
#define YY_BUFFER_EOF_PENDING 2
    };

static YY_BUFFER_STATE yy_current_buffer = 0;

/* We provide macros for accessing buffer states in case in the
 * future we want to put the buffer states in a more general
 * "scanner state".
 */
#define YY_CURRENT_BUFFER yy_current_buffer


/* yy_hold_char holds the character lost when yytext is formed. */
static char yy_hold_char;

static int yy_n_chars;        /* number of characters read into yy_ch_buf */


int yyleng;

/* Points to current character in buffer. */
static char *yy_c_buf_p = (char *) 0;
static int yy_init = 1;        /* whether we need to initialize */
static int yy_start = 0;    /* start state number */

/* Flag which is used to allow yywrap()'s to do buffer switches
 * instead of setting up a fresh yyin.  A bit of a hack ...
 */
static int yy_did_buffer_switch_on_eof;

void yyrestart YY_PROTO(( FILE *input_file ));

void yy_switch_to_buffer YY_PROTO(( YY_BUFFER_STATE new_buffer ));
void yy_load_buffer_state YY_PROTO(( void ));
YY_BUFFER_STATE yy_create_buffer YY_PROTO(( FILE *file, int size ));
void yy_delete_buffer YY_PROTO(( YY_BUFFER_STATE b ));
void yy_init_buffer YY_PROTO(( YY_BUFFER_STATE b, FILE *file ));
void yy_flush_buffer YY_PROTO(( YY_BUFFER_STATE b ));
#define YY_FLUSH_BUFFER yy_flush_buffer( yy_current_buffer )

YY_BUFFER_STATE yy_scan_buffer YY_PROTO(( char *base, yy_size_t size ));
YY_BUFFER_STATE yy_scan_string YY_PROTO(( yyconst char *str ));
YY_BUFFER_STATE yy_scan_bytes YY_PROTO(( yyconst char *bytes, int len ));

static void *yy_flex_alloc YY_PROTO(( yy_size_t ));
static void *yy_flex_realloc YY_PROTO(( void *, yy_size_t ));
static void yy_flex_free YY_PROTO(( void * ));

#define yy_new_buffer yy_create_buffer

#define yy_set_interactive(is_interactive) \
    { \
    if ( ! yy_current_buffer ) \
        yy_current_buffer = yy_create_buffer( yyin, YY_BUF_SIZE ); \
    yy_current_buffer->yy_is_interactive = is_interactive; \
    }

#define yy_set_bol(at_bol) \
    { \
    if ( ! yy_current_buffer ) \
        yy_current_buffer = yy_create_buffer( yyin, YY_BUF_SIZE ); \
    yy_current_buffer->yy_at_bol = at_bol; \
    }

#define YY_AT_BOL() (yy_current_buffer->yy_at_bol)


#define yywrap() 1
#define YY_SKIP_YYWRAP
typedef unsigned char YY_CHAR;
FILE *yyin = (FILE *) 0, *yyout = (FILE *) 0;
typedef int yy_state_type;
extern char *yytext;
#define yytext_ptr yytext

static yy_state_type yy_get_previous_state YY_PROTO(( void ));
static yy_state_type yy_try_NUL_trans YY_PROTO(( yy_state_type current_state ));
static int yy_get_next_buffer YY_PROTO(( void ));
static void yy_fatal_error YY_PROTO(( yyconst char msg[] ));

/* Done after the current pattern has been matched and before the
 * corresponding action - sets up yytext.
 */
#define YY_DO_BEFORE_ACTION \
    yytext_ptr = yy_bp; \
    yyleng = (int) (yy_cp - yy_bp); \
    yy_hold_char = *yy_cp; \
    *yy_cp = '\0'; \
    yy_c_buf_p = yy_cp;

#define YY_NUM_RULES 6
#define YY_END_OF_BUFFER 7
static yyconst short int yy_accept[12] =
    {   0,
        0,    0,    7,    5,    4,    4,    1,    2,    3,    3,
        0
    } ;

static yyconst int yy_ec[256] =
    {   0,
        1,    1,    1,    1,    1,    1,    1,    1,    2,    3,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    2,    1,    1,    4,    1,    1,    1,    1,    5,
        5,    5,    5,    1,    1,    1,    1,    6,    7,    7,
        7,    7,    7,    7,    7,    7,    7,    1,    1,    1,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,

        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,

        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    1,    1,    1,    1,    1,    1,    1,    1,    1,
        1,    1,    1,    1,    1
    } ;

static yyconst int yy_meta[8] =
    {   0,
        1,    1,    1,    1,    1,    2,    2
    } ;

static yyconst short int yy_base[13] =
    {   0,
        0,    0,    9,   10,   10,   10,   10,   10,    0,    0,
       10,    6
    } ;

static yyconst short int yy_def[13] =
    {   0,
       11,    1,   11,   11,   11,   11,   11,   11,   12,   12,
        0,   11
    } ;

static yyconst short int yy_nxt[18] =
    {   0,
        4,    5,    6,    7,    8,    4,    9,   10,   11,    3,
       11,   11,   11,   11,   11,   11,   11
    } ;

static yyconst short int yy_chk[18] =
    {   0,
        1,    1,    1,    1,    1,    1,    1,   12,    3,   11,
       11,   11,   11,   11,   11,   11,   11
    } ;

static yy_state_type yy_last_accepting_state;
static char *yy_last_accepting_cpos;

/* The intent behind this definition is that it'll catch
 * any uses of REJECT which flex missed.
 */
#define REJECT reject_used_but_not_detected
#define yymore() yymore_used_but_not_detected
#define YY_MORE_ADJ 0
char *yytext;
#line 1 "D:\\中缀\\词法分析.txt"
#define INITIAL 0
#line 3 "D:\\中缀\\词法分析.txt"
    #include <stdio.h>
       #include <stdlib.h>
    int num=0;
       int num_num = 0;
       int num_op = 0;
       int aa[200]={0};
       char cc[200]={0};
#line 377 "lex.yy.c"

/* Macros after this point can all be overridden by user definitions in
 * section 1.
 */

#ifndef YY_SKIP_YYWRAP
#ifdef __cplusplus
extern "C" int yywrap YY_PROTO(( void ));
#else
extern int yywrap YY_PROTO(( void ));
#endif
#endif

#ifndef YY_NO_UNPUT
static void yyunput YY_PROTO(( int c, char *buf_ptr ));
#endif

#ifndef yytext_ptr
static void yy_flex_strncpy YY_PROTO(( char *, yyconst char *, int ));
#endif

#ifndef YY_NO_INPUT
#ifdef __cplusplus
static int yyinput YY_PROTO(( void ));
#else
static int input YY_PROTO(( void ));
#endif
#endif

#if YY_STACK_USED
static int yy_start_stack_ptr = 0;
static int yy_start_stack_depth = 0;
static int *yy_start_stack = 0;
#ifndef YY_NO_PUSH_STATE
static void yy_push_state YY_PROTO(( int new_state ));
#endif
#ifndef YY_NO_POP_STATE
static void yy_pop_state YY_PROTO(( void ));
#endif
#ifndef YY_NO_TOP_STATE
static int yy_top_state YY_PROTO(( void ));
#endif

#else
#define YY_NO_PUSH_STATE 1
#define YY_NO_POP_STATE 1
#define YY_NO_TOP_STATE 1
#endif

#ifdef YY_MALLOC_DECL
YY_MALLOC_DECL
#else
#if __STDC__
#ifndef __cplusplus
#include <stdlib.h>
#endif
#else
/* Just try to get by without declaring the routines.  This will fail
 * miserably on non-ANSI systems for which sizeof(size_t) != sizeof(int)
 * or sizeof(void*) != sizeof(int).
 */
#endif
#endif

/* Amount of stuff to slurp up with each read. */
#ifndef YY_READ_BUF_SIZE
#define YY_READ_BUF_SIZE 8192
#endif

/* Copy whatever the last rule matched to the standard output. */

#ifndef ECHO
/* This used to be an fputs(), but since the string might contain NUL's,
 * we now use fwrite().
 */
#define ECHO (void) fwrite( yytext, yyleng, 1, yyout )
#endif

/* Gets input and stuffs it into "buf".  number of characters read, or YY_NULL,
 * is returned in "result".
 */
#ifndef YY_INPUT
#define YY_INPUT(buf,result,max_size) \
    if ( yy_current_buffer->yy_is_interactive ) \
        { \
        int c = '*', n; \
        for ( n = 0; n < max_size && \
                 (c = getc( yyin )) != EOF && c != '\n'; ++n ) \
            buf[n] = (char) c; \
        if ( c == '\n' ) \
            buf[n++] = (char) c; \
        if ( c == EOF && ferror( yyin ) ) \
            YY_FATAL_ERROR( "input in flex scanner failed" ); \
        result = n; \
        } \
    else if ( ((result = fread( buf, 1, max_size, yyin )) == 0) \
          && ferror( yyin ) ) \
        YY_FATAL_ERROR( "input in flex scanner failed" );
#endif

/* No semi-colon after return; correct usage is to write "yyterminate();" -
 * we don't want an extra ';' after the "return" because that will cause
 * some compilers to complain about unreachable statements.
 */
#ifndef yyterminate
#define yyterminate() return YY_NULL
#endif

/* Number of entries by which start-condition stack grows. */
#ifndef YY_START_STACK_INCR
#define YY_START_STACK_INCR 25
#endif

/* Report a fatal error. */
#ifndef YY_FATAL_ERROR
#define YY_FATAL_ERROR(msg) yy_fatal_error( msg )
#endif

/* Default declaration of generated scanner - a define so the user can
 * easily add parameters.
 */
#ifndef YY_DECL
#define YY_DECL int yylex YY_PROTO(( void ))
#endif

/* Code executed at the beginning of each rule, after yytext and yyleng
 * have been set up.
 */
#ifndef YY_USER_ACTION
#define YY_USER_ACTION
#endif

/* Code executed at the end of each rule. */
#ifndef YY_BREAK
#define YY_BREAK break;
#endif

#define YY_RULE_SETUP \
    YY_USER_ACTION

YY_DECL
    {
    register yy_state_type yy_current_state;
    register char *yy_cp, *yy_bp;
    register int yy_act;

#line 22 "D:\\中缀\\词法分析.txt"

#line 526 "lex.yy.c"

    if ( yy_init )
        {
        yy_init = 0;

#ifdef YY_USER_INIT
        YY_USER_INIT;
#endif

        if ( ! yy_start )
            yy_start = 1;    /* first start state */

        if ( ! yyin )
            yyin = stdin;

        if ( ! yyout )
            yyout = stdout;

        if ( ! yy_current_buffer )
            yy_current_buffer =
                yy_create_buffer( yyin, YY_BUF_SIZE );

        yy_load_buffer_state();
        }

    while ( 1 )        /* loops until end-of-file is reached */
        {
        yy_cp = yy_c_buf_p;

        /* Support of yytext. */
        *yy_cp = yy_hold_char;

        /* yy_bp points to the position in yy_ch_buf of the start of
         * the current run.
         */
        yy_bp = yy_cp;

        yy_current_state = yy_start;
yy_match:
        do
            {
            register YY_CHAR yy_c = yy_ec[YY_SC_TO_UI(*yy_cp)];
            if ( yy_accept[yy_current_state] )
                {
                yy_last_accepting_state = yy_current_state;
                yy_last_accepting_cpos = yy_cp;
                }
            while ( yy_chk[yy_base[yy_current_state] + yy_c] != yy_current_state )
                {
                yy_current_state = (int) yy_def[yy_current_state];
                if ( yy_current_state >= 12 )
                    yy_c = yy_meta[(unsigned int) yy_c];
                }
            yy_current_state = yy_nxt[yy_base[yy_current_state] + (unsigned int) yy_c];
            ++yy_cp;
            }
        while ( yy_base[yy_current_state] != 10 );

yy_find_action:
        yy_act = yy_accept[yy_current_state];
        if ( yy_act == 0 )
            { /* have to back up */
            yy_cp = yy_last_accepting_cpos;
            yy_current_state = yy_last_accepting_state;
            yy_act = yy_accept[yy_current_state];
            }

        YY_DO_BEFORE_ACTION;


do_action:    /* This label is used only to access EOF actions. */


        switch ( yy_act )
    { /* beginning of action switch */
            case 0: /* must back up */
            /* undo the effects of YY_DO_BEFORE_ACTION */
            *yy_cp = yy_hold_char;
            yy_cp = yy_last_accepting_cpos;
            yy_current_state = yy_last_accepting_state;
            goto yy_find_action;

case 1:
YY_RULE_SETUP
#line 23 "D:\\中缀\\词法分析.txt"
{
    return 0;
}
    YY_BREAK
case 2:
YY_RULE_SETUP
#line 26 "D:\\中缀\\词法分析.txt"
{
    cc[num]=*yytext;
    num++;

}
    YY_BREAK
case 3:
YY_RULE_SETUP
#line 32 "D:\\中缀\\词法分析.txt"
{

    aa[num_num]=atoi(yytext);
    cc[num]='i';
    num++;
      num_num++;

    /*数字数加一*/

}
    YY_BREAK
case 4:
YY_RULE_SETUP
#line 46 "D:\\中缀\\词法分析.txt"
{

   /*什么也不做,滤掉白字符和其它字符*/

}
    YY_BREAK
case 5:
YY_RULE_SETUP
#line 51 "D:\\中缀\\词法分析.txt"
{
    printf("error\n");
}
    YY_BREAK
case 6:
YY_RULE_SETUP
#line 54 "D:\\中缀\\词法分析.txt"
ECHO;
    YY_BREAK
#line 660 "lex.yy.c"
case YY_STATE_EOF(INITIAL):
    yyterminate();

    case YY_END_OF_BUFFER:
        {
        /* Amount of text matched not including the EOB char. */
        int yy_amount_of_matched_text = (int) (yy_cp - yytext_ptr) - 1;

        /* Undo the effects of YY_DO_BEFORE_ACTION. */
        *yy_cp = yy_hold_char;

        if ( yy_current_buffer->yy_buffer_status == YY_BUFFER_NEW )
            {
            /* We're scanning a new file or input source.  It's
             * possible that this happened because the user
             * just pointed yyin at a new source and called
             * yylex().  If so, then we have to assure
             * consistency between yy_current_buffer and our
             * globals.  Here is the right place to do so, because
             * this is the first action (other than possibly a
             * back-up) that will match for the new input source.
             */
            yy_n_chars = yy_current_buffer->yy_n_chars;
            yy_current_buffer->yy_input_file = yyin;
            yy_current_buffer->yy_buffer_status = YY_BUFFER_NORMAL;
            }

        /* Note that here we test for yy_c_buf_p "<=" to the position
         * of the first EOB in the buffer, since yy_c_buf_p will
         * already have been incremented past the NUL character
         * (since all states make transitions on EOB to the
         * end-of-buffer state).  Contrast this with the test
         * in input().
         */
        if ( yy_c_buf_p <= &yy_current_buffer->yy_ch_buf[yy_n_chars] )
            { /* This was really a NUL. */
            yy_state_type yy_next_state;

            yy_c_buf_p = yytext_ptr + yy_amount_of_matched_text;

            yy_current_state = yy_get_previous_state();

            /* Okay, we're now positioned to make the NUL
             * transition.  We couldn't have
             * yy_get_previous_state() go ahead and do it
             * for us because it doesn't know how to deal
             * with the possibility of jamming (and we don't
             * want to build jamming into it because then it
             * will run more slowly).
             */

            yy_next_state = yy_try_NUL_trans( yy_current_state );

            yy_bp = yytext_ptr + YY_MORE_ADJ;

            if ( yy_next_state )
                {
                /* Consume the NUL. */
                yy_cp = ++yy_c_buf_p;
                yy_current_state = yy_next_state;
                goto yy_match;
                }

            else
                {
                yy_cp = yy_c_buf_p;
                goto yy_find_action;
                }
            }

        else switch ( yy_get_next_buffer() )
            {
            case EOB_ACT_END_OF_FILE:
                {
                yy_did_buffer_switch_on_eof = 0;

                if ( yywrap() )
                    {
                    /* Note: because we've taken care in
                     * yy_get_next_buffer() to have set up
                     * yytext, we can now set up
                     * yy_c_buf_p so that if some total
                     * hoser (like flex itself) wants to
                     * call the scanner after we return the
                     * YY_NULL, it'll still work - another
                     * YY_NULL will get returned.
                     */
                    yy_c_buf_p = yytext_ptr + YY_MORE_ADJ;

                    yy_act = YY_STATE_EOF(YY_START);
                    goto do_action;
                    }

                else
                    {
                    if ( ! yy_did_buffer_switch_on_eof )
                        YY_NEW_FILE;
                    }
                break;
                }

            case EOB_ACT_CONTINUE_SCAN:
                yy_c_buf_p =
                    yytext_ptr + yy_amount_of_matched_text;

                yy_current_state = yy_get_previous_state();

                yy_cp = yy_c_buf_p;
                yy_bp = yytext_ptr + YY_MORE_ADJ;
                goto yy_match;

            case EOB_ACT_LAST_MATCH:
                yy_c_buf_p =
                &yy_current_buffer->yy_ch_buf[yy_n_chars];

                yy_current_state = yy_get_previous_state();

                yy_cp = yy_c_buf_p;
                yy_bp = yytext_ptr + YY_MORE_ADJ;
                goto yy_find_action;
            }
        break;
        }

    default:
        YY_FATAL_ERROR(
            "fatal flex scanner internal error--no action found" );
    } /* end of action switch */
        } /* end of scanning one token */
    } /* end of yylex */


/* yy_get_next_buffer - try to read in a new buffer
 *
 * Returns a code representing an action:
 *    EOB_ACT_LAST_MATCH -
 *    EOB_ACT_CONTINUE_SCAN - continue scanning from current position
 *    EOB_ACT_END_OF_FILE - end of file
 */

static int yy_get_next_buffer()
    {
    register char *dest = yy_current_buffer->yy_ch_buf;
    register char *source = yytext_ptr;
    register int number_to_move, i;
    int ret_val;

    if ( yy_c_buf_p > &yy_current_buffer->yy_ch_buf[yy_n_chars + 1] )
        YY_FATAL_ERROR(
        "fatal flex scanner internal error--end of buffer missed" );

    if ( yy_current_buffer->yy_fill_buffer == 0 )
        { /* Don't try to fill the buffer, so this is an EOF. */
        if ( yy_c_buf_p - yytext_ptr - YY_MORE_ADJ == 1 )
            {
            /* We matched a singled characater, the EOB, so
             * treat this as a final EOF.
             */
            return EOB_ACT_END_OF_FILE;
            }

        else
            {
            /* We matched some text prior to the EOB, first
             * process it.
             */
            return EOB_ACT_LAST_MATCH;
            }
        }

    /* Try to read more data. */

    /* First move last chars to start of buffer. */
    number_to_move = (int) (yy_c_buf_p - yytext_ptr) - 1;

    for ( i = 0; i < number_to_move; ++i )
        *(dest++) = *(source++);

    if ( yy_current_buffer->yy_buffer_status == YY_BUFFER_EOF_PENDING )
        /* don't do the read, it's not guaranteed to return an EOF,
         * just force an EOF
         */
        yy_n_chars = 0;

    else
        {
        int num_to_read =
            yy_current_buffer->yy_buf_size - number_to_move - 1;

        while ( num_to_read <= 0 )
            { /* Not enough room in the buffer - grow it. */
#ifdef YY_USES_REJECT
            YY_FATAL_ERROR(
"input buffer overflow, can't enlarge buffer because scanner uses REJECT" );
#else

            /* just a shorter name for the current buffer */
            YY_BUFFER_STATE b = yy_current_buffer;

            int yy_c_buf_p_offset =
                (int) (yy_c_buf_p - b->yy_ch_buf);

            if ( b->yy_is_our_buffer )
                {
                int new_size = b->yy_buf_size * 2;

                if ( new_size <= 0 )
                    b->yy_buf_size += b->yy_buf_size / 8;
                else
                    b->yy_buf_size *= 2;

                b->yy_ch_buf = (char *)
                    /* Include room in for 2 EOB chars. */
                    yy_flex_realloc( (void *) b->yy_ch_buf,
                             b->yy_buf_size + 2 );
                }
            else
                /* Can't grow it, we don't own it. */
                b->yy_ch_buf = 0;

            if ( ! b->yy_ch_buf )
                YY_FATAL_ERROR(
                "fatal error - scanner input buffer overflow" );

            yy_c_buf_p = &b->yy_ch_buf[yy_c_buf_p_offset];

            num_to_read = yy_current_buffer->yy_buf_size -
                        number_to_move - 1;
#endif
            }

        if ( num_to_read > YY_READ_BUF_SIZE )
            num_to_read = YY_READ_BUF_SIZE;

        /* Read in more data. */
        YY_INPUT( (&yy_current_buffer->yy_ch_buf[number_to_move]),
            yy_n_chars, num_to_read );
        }

    if ( yy_n_chars == 0 )
        {
        if ( number_to_move == YY_MORE_ADJ )
            {
            ret_val = EOB_ACT_END_OF_FILE;
            yyrestart( yyin );
            }

        else
            {
            ret_val = EOB_ACT_LAST_MATCH;
            yy_current_buffer->yy_buffer_status =
                YY_BUFFER_EOF_PENDING;
            }
        }

    else
        ret_val = EOB_ACT_CONTINUE_SCAN;

    yy_n_chars += number_to_move;
    yy_current_buffer->yy_ch_buf[yy_n_chars] = YY_END_OF_BUFFER_CHAR;
    yy_current_buffer->yy_ch_buf[yy_n_chars + 1] = YY_END_OF_BUFFER_CHAR;

    yytext_ptr = &yy_current_buffer->yy_ch_buf[0];

    return ret_val;
    }


/* yy_get_previous_state - get the state just before the EOB char was reached */

static yy_state_type yy_get_previous_state()
    {
    register yy_state_type yy_current_state;
    register char *yy_cp;

    yy_current_state = yy_start;

    for ( yy_cp = yytext_ptr + YY_MORE_ADJ; yy_cp < yy_c_buf_p; ++yy_cp )
        {
        register YY_CHAR yy_c = (*yy_cp ? yy_ec[YY_SC_TO_UI(*yy_cp)] : 1);
        if ( yy_accept[yy_current_state] )
            {
            yy_last_accepting_state = yy_current_state;
            yy_last_accepting_cpos = yy_cp;
            }
        while ( yy_chk[yy_base[yy_current_state] + yy_c] != yy_current_state )
            {
            yy_current_state = (int) yy_def[yy_current_state];
            if ( yy_current_state >= 12 )
                yy_c = yy_meta[(unsigned int) yy_c];
            }
        yy_current_state = yy_nxt[yy_base[yy_current_state] + (unsigned int) yy_c];
        }

    return yy_current_state;
    }


/* yy_try_NUL_trans - try to make a transition on the NUL character
 *
 * synopsis
 *    next_state = yy_try_NUL_trans( current_state );
 */

#ifdef YY_USE_PROTOS
static yy_state_type yy_try_NUL_trans( yy_state_type yy_current_state )
#else
static yy_state_type yy_try_NUL_trans( yy_current_state )
yy_state_type yy_current_state;
#endif
    {
    register int yy_is_jam;
    register char *yy_cp = yy_c_buf_p;

    register YY_CHAR yy_c = 1;
    if ( yy_accept[yy_current_state] )
        {
        yy_last_accepting_state = yy_current_state;
        yy_last_accepting_cpos = yy_cp;
        }
    while ( yy_chk[yy_base[yy_current_state] + yy_c] != yy_current_state )
        {
        yy_current_state = (int) yy_def[yy_current_state];
        if ( yy_current_state >= 12 )
            yy_c = yy_meta[(unsigned int) yy_c];
        }
    yy_current_state = yy_nxt[yy_base[yy_current_state] + (unsigned int) yy_c];
    yy_is_jam = (yy_current_state == 11);

    return yy_is_jam ? 0 : yy_current_state;
    }


#ifndef YY_NO_UNPUT
#ifdef YY_USE_PROTOS
static void yyunput( int c, register char *yy_bp )
#else
static void yyunput( c, yy_bp )
int c;
register char *yy_bp;
#endif
    {
    register char *yy_cp = yy_c_buf_p;

    /* undo effects of setting up yytext */
    *yy_cp = yy_hold_char;

    if ( yy_cp < yy_current_buffer->yy_ch_buf + 2 )
        { /* need to shift things up to make room */
        /* +2 for EOB chars. */
        register int number_to_move = yy_n_chars + 2;
        register char *dest = &yy_current_buffer->yy_ch_buf[
                    yy_current_buffer->yy_buf_size + 2];
        register char *source =
                &yy_current_buffer->yy_ch_buf[number_to_move];

        while ( source > yy_current_buffer->yy_ch_buf )
            *--dest = *--source;

        yy_cp += (int) (dest - source);
        yy_bp += (int) (dest - source);
        yy_n_chars = yy_current_buffer->yy_buf_size;

        if ( yy_cp < yy_current_buffer->yy_ch_buf + 2 )
            YY_FATAL_ERROR( "flex scanner push-back overflow" );
        }

    *--yy_cp = (char) c;


    yytext_ptr = yy_bp;
    yy_hold_char = *yy_cp;
    yy_c_buf_p = yy_cp;
    }
#endif    /* ifndef YY_NO_UNPUT */


#ifdef __cplusplus
static int yyinput()
#else
static int input()
#endif
    {
    int c;

    *yy_c_buf_p = yy_hold_char;

    if ( *yy_c_buf_p == YY_END_OF_BUFFER_CHAR )
        {
        /* yy_c_buf_p now points to the character we want to return.
         * If this occurs *before* the EOB characters, then it's a
         * valid NUL; if not, then we've hit the end of the buffer.
         */
        if ( yy_c_buf_p < &yy_current_buffer->yy_ch_buf[yy_n_chars] )
            /* This was really a NUL. */
            *yy_c_buf_p = '\0';

        else
            { /* need more input */
            yytext_ptr = yy_c_buf_p;
            ++yy_c_buf_p;

            switch ( yy_get_next_buffer() )
                {
                case EOB_ACT_END_OF_FILE:
                    {
                    if ( yywrap() )
                        {
                        yy_c_buf_p =
                        yytext_ptr + YY_MORE_ADJ;
                        return EOF;
                        }

                    if ( ! yy_did_buffer_switch_on_eof )
                        YY_NEW_FILE;
#ifdef __cplusplus
                    return yyinput();
#else
                    return input();
#endif
                    }

                case EOB_ACT_CONTINUE_SCAN:
                    yy_c_buf_p = yytext_ptr + YY_MORE_ADJ;
                    break;

                case EOB_ACT_LAST_MATCH:
#ifdef __cplusplus
                    YY_FATAL_ERROR(
                    "unexpected last match in yyinput()" );
#else
                    YY_FATAL_ERROR(
                    "unexpected last match in input()" );
#endif
                }
            }
        }

    c = *(unsigned char *) yy_c_buf_p;    /* cast for 8-bit char's */
    *yy_c_buf_p = '\0';    /* preserve yytext */
    yy_hold_char = *++yy_c_buf_p;


    return c;
    }


#ifdef YY_USE_PROTOS
void yyrestart( FILE *input_file )
#else
void yyrestart( input_file )
FILE *input_file;
#endif
    {
    if ( ! yy_current_buffer )
        yy_current_buffer = yy_create_buffer( yyin, YY_BUF_SIZE );

    yy_init_buffer( yy_current_buffer, input_file );
    yy_load_buffer_state();
    }


#ifdef YY_USE_PROTOS
void yy_switch_to_buffer( YY_BUFFER_STATE new_buffer )
#else
void yy_switch_to_buffer( new_buffer )
YY_BUFFER_STATE new_buffer;
#endif
    {
    if ( yy_current_buffer == new_buffer )
        return;

    if ( yy_current_buffer )
        {
        /* Flush out information for old buffer. */
        *yy_c_buf_p = yy_hold_char;
        yy_current_buffer->yy_buf_pos = yy_c_buf_p;
        yy_current_buffer->yy_n_chars = yy_n_chars;
        }

    yy_current_buffer = new_buffer;
    yy_load_buffer_state();

    /* We don't actually know whether we did this switch during
     * EOF (yywrap()) processing, but the only time this flag
     * is looked at is after yywrap() is called, so it's safe
     * to go ahead and always set it.
     */
    yy_did_buffer_switch_on_eof = 1;
    }


#ifdef YY_USE_PROTOS
void yy_load_buffer_state( void )
#else
void yy_load_buffer_state()
#endif
    {
    yy_n_chars = yy_current_buffer->yy_n_chars;
    yytext_ptr = yy_c_buf_p = yy_current_buffer->yy_buf_pos;
    yyin = yy_current_buffer->yy_input_file;
    yy_hold_char = *yy_c_buf_p;
    }


#ifdef YY_USE_PROTOS
YY_BUFFER_STATE yy_create_buffer( FILE *file, int size )
#else
YY_BUFFER_STATE yy_create_buffer( file, size )
FILE *file;
int size;
#endif
    {
    YY_BUFFER_STATE b;

    b = (YY_BUFFER_STATE) yy_flex_alloc( sizeof( struct yy_buffer_state ) );
    if ( ! b )
        YY_FATAL_ERROR( "out of dynamic memory in yy_create_buffer()" );

    b->yy_buf_size = size;

    /* yy_ch_buf has to be 2 characters longer than the size given because
     * we need to put in 2 end-of-buffer characters.
     */
    b->yy_ch_buf = (char *) yy_flex_alloc( b->yy_buf_size + 2 );
    if ( ! b->yy_ch_buf )
        YY_FATAL_ERROR( "out of dynamic memory in yy_create_buffer()" );

    b->yy_is_our_buffer = 1;

    yy_init_buffer( b, file );

    return b;
    }


#ifdef YY_USE_PROTOS
void yy_delete_buffer( YY_BUFFER_STATE b )
#else
void yy_delete_buffer( b )
YY_BUFFER_STATE b;
#endif
    {
    if ( ! b )
        return;

    if ( b == yy_current_buffer )
        yy_current_buffer = (YY_BUFFER_STATE) 0;

    if ( b->yy_is_our_buffer )
        yy_flex_free( (void *) b->yy_ch_buf );

    yy_flex_free( (void *) b );
    }


#ifndef YY_ALWAYS_INTERACTIVE
#ifndef YY_NEVER_INTERACTIVE
extern int isatty YY_PROTO(( int ));
#endif
#endif

#ifdef YY_USE_PROTOS
void yy_init_buffer( YY_BUFFER_STATE b, FILE *file )
#else
void yy_init_buffer( b, file )
YY_BUFFER_STATE b;
FILE *file;
#endif


    {
    yy_flush_buffer( b );

    b->yy_input_file = file;
    b->yy_fill_buffer = 1;

#if YY_ALWAYS_INTERACTIVE
    b->yy_is_interactive = 1;
#else
#if YY_NEVER_INTERACTIVE
    b->yy_is_interactive = 0;
#else
    b->yy_is_interactive = file ? (isatty( fileno(file) ) > 0) : 0;
#endif
#endif
    }


#ifdef YY_USE_PROTOS
void yy_flush_buffer( YY_BUFFER_STATE b )
#else
void yy_flush_buffer( b )
YY_BUFFER_STATE b;
#endif

    {
    b->yy_n_chars = 0;

    /* We always need two end-of-buffer characters.  The first causes
     * a transition to the end-of-buffer state.  The second causes
     * a jam in that state.
     */
    b->yy_ch_buf[0] = YY_END_OF_BUFFER_CHAR;
    b->yy_ch_buf[1] = YY_END_OF_BUFFER_CHAR;

    b->yy_buf_pos = &b->yy_ch_buf[0];

    b->yy_at_bol = 1;
    b->yy_buffer_status = YY_BUFFER_NEW;

    if ( b == yy_current_buffer )
        yy_load_buffer_state();
    }


#ifndef YY_NO_SCAN_BUFFER
#ifdef YY_USE_PROTOS
YY_BUFFER_STATE yy_scan_buffer( char *base, yy_size_t size )
#else
YY_BUFFER_STATE yy_scan_buffer( base, size )
char *base;
yy_size_t size;
#endif
    {
    YY_BUFFER_STATE b;

    if ( size < 2 ||
         base[size-2] != YY_END_OF_BUFFER_CHAR ||
         base[size-1] != YY_END_OF_BUFFER_CHAR )
        /* They forgot to leave room for the EOB's. */
        return 0;

    b = (YY_BUFFER_STATE) yy_flex_alloc( sizeof( struct yy_buffer_state ) );
    if ( ! b )
        YY_FATAL_ERROR( "out of dynamic memory in yy_scan_buffer()" );

    b->yy_buf_size = size - 2;    /* "- 2" to take care of EOB's */
    b->yy_buf_pos = b->yy_ch_buf = base;
    b->yy_is_our_buffer = 0;
    b->yy_input_file = 0;
    b->yy_n_chars = b->yy_buf_size;
    b->yy_is_interactive = 0;
    b->yy_at_bol = 1;
    b->yy_fill_buffer = 0;
    b->yy_buffer_status = YY_BUFFER_NEW;

    yy_switch_to_buffer( b );

    return b;
    }
#endif


#ifndef YY_NO_SCAN_STRING
#ifdef YY_USE_PROTOS
YY_BUFFER_STATE yy_scan_string( yyconst char *str )
#else
YY_BUFFER_STATE yy_scan_string( str )
yyconst char *str;
#endif
    {
    int len;
    for ( len = 0; str[len]; ++len )
        ;

    return yy_scan_bytes( str, len );
    }
#endif


#ifndef YY_NO_SCAN_BYTES
#ifdef YY_USE_PROTOS
YY_BUFFER_STATE yy_scan_bytes( yyconst char *bytes, int len )
#else
YY_BUFFER_STATE yy_scan_bytes( bytes, len )
yyconst char *bytes;
int len;
#endif
    {
    YY_BUFFER_STATE b;
    char *buf;
    yy_size_t n;
    int i;

    /* Get memory for full buffer, including space for trailing EOB's. */
    n = len + 2;
    buf = (char *) yy_flex_alloc( n );
    if ( ! buf )
        YY_FATAL_ERROR( "out of dynamic memory in yy_scan_bytes()" );

    for ( i = 0; i < len; ++i )
        buf[i] = bytes[i];

    buf[len] = buf[len+1] = YY_END_OF_BUFFER_CHAR;

    b = yy_scan_buffer( buf, n );
    if ( ! b )
        YY_FATAL_ERROR( "bad buffer in yy_scan_bytes()" );

    /* It's okay to grow etc. this buffer, and we should throw it
     * away when we're done.
     */
    b->yy_is_our_buffer = 1;

    return b;
    }
#endif


#ifndef YY_NO_PUSH_STATE
#ifdef YY_USE_PROTOS
static void yy_push_state( int new_state )
#else
static void yy_push_state( new_state )
int new_state;
#endif
    {
    if ( yy_start_stack_ptr >= yy_start_stack_depth )
        {
        yy_size_t new_size;

        yy_start_stack_depth += YY_START_STACK_INCR;
        new_size = yy_start_stack_depth * sizeof( int );

        if ( ! yy_start_stack )
            yy_start_stack = (int *) yy_flex_alloc( new_size );

        else
            yy_start_stack = (int *) yy_flex_realloc(
                    (void *) yy_start_stack, new_size );

        if ( ! yy_start_stack )
            YY_FATAL_ERROR(
            "out of memory expanding start-condition stack" );
        }

    yy_start_stack[yy_start_stack_ptr++] = YY_START;

    BEGIN(new_state);
    }
#endif


#ifndef YY_NO_POP_STATE
static void yy_pop_state()
    {
    if ( --yy_start_stack_ptr < 0 )
        YY_FATAL_ERROR( "start-condition stack underflow" );

    BEGIN(yy_start_stack[yy_start_stack_ptr]);
    }
#endif


#ifndef YY_NO_TOP_STATE
static int yy_top_state()
    {
    return yy_start_stack[yy_start_stack_ptr - 1];
    }
#endif

#ifndef YY_EXIT_FAILURE
#define YY_EXIT_FAILURE 2
#endif

#ifdef YY_USE_PROTOS
static void yy_fatal_error( yyconst char msg[] )
#else
static void yy_fatal_error( msg )
char msg[];
#endif
    {
    (void) fprintf( stderr, "%s\n", msg );
    exit( YY_EXIT_FAILURE );
    }

/* Redefine yyless() so it works in section 3 code. */

#undef yyless
#define yyless(n) \
    do \
        { \
        /* Undo effects of setting up yytext. */ \
        yytext[yyleng] = yy_hold_char; \
        yy_c_buf_p = yytext + n - YY_MORE_ADJ; \
        yy_hold_char = *yy_c_buf_p; \
        *yy_c_buf_p = '\0'; \
        yyleng = n; \
        } \
    while ( 0 )


/* Internal utility routines. */

#ifndef yytext_ptr
#ifdef YY_USE_PROTOS
static void yy_flex_strncpy( char *s1, yyconst char *s2, int n )
#else
static void yy_flex_strncpy( s1, s2, n )
char *s1;
yyconst char *s2;
int n;
#endif
    {
    register int i;
    for ( i = 0; i < n; ++i )
        s1[i] = s2[i];
    }
#endif


#ifdef YY_USE_PROTOS
static void *yy_flex_alloc( yy_size_t size )
#else
static void *yy_flex_alloc( size )
yy_size_t size;
#endif
    {
    return (void *) malloc( size );
    }

#ifdef YY_USE_PROTOS
static void *yy_flex_realloc( void *ptr, yy_size_t size )
#else
static void *yy_flex_realloc( ptr, size )
void *ptr;
yy_size_t size;
#endif
    {
    /* The cast to (char *) in the following accommodates both
     * implementations that use char* generic pointers, and those
     * that use void* generic pointers.  It works with the latter
     * because both ANSI C and C++ allow castless assignment from
     * any pointer type to void*, and deal with argument conversions
     * as though doing an assignment.
     */
    return (void *) realloc( (char *) ptr, size );
    }

#ifdef YY_USE_PROTOS
static void yy_flex_free( void *ptr )
#else
static void yy_flex_free( ptr )
void *ptr;
#endif
    {
    free( ptr );
    }

#if YY_MAIN
int main()
    {
    yylex();
    return 0;
    }
#endif
#line 54 "D:\\中缀\\词法分析.txt"


int www()

{
    yylex();
     return 0;

}
 

 

 

【编译原理】扩展试验_语法制导翻译_2_B_2.将表达式翻译为后缀式-LR分析【编译原理】扩展试验_语法制导翻译_2_B_2.将表达式翻译为后缀式-LR分析 涂山北枫 发布了38 篇原创文章 · 获赞 27 · 访问量 2万+ 私信 关注
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