编译原理实验1扫描器的设计与实现

；words[j]=\0flag=；}415else flag=416;；break}case/{if ch==7；words[j++]=chwords[j]=5\09;；ch=program[i++]ifch==-9{words[j++]=ch;；words[j]=\0flag=417;else flag=418;break;；case{words[j]=ch;words[j+1]=\0;flag=501;；break}{case words[j]；=ch；words[j+l]=\0flag=；502break;case{words[j]=ch;words[j+1]=\T;flag=503;break;case*[1:{words[j]=ch;words[j+l]=,\0,;flag=504;break;case]{words[j]=ch;，；words[j+1]=T flag；；=505break case*{*{words[j]=；，；ch words[j+1]=\0；；flag=506breakcase}:{words[j]=ch;words[j+l]=,\0,；flag=507;；breakcase:{words[j]=ch;，；words[j+1]=\X flag=508;；}breakcase””:{words[j]=ch;，；；words[j+1]=\0flag=509；break，％，；case{if ch==%words[j++]=chwords[j]=*\09；；ch=program[i++]if ch==words[j++]=ch；words[j]=*\05;flag=510;else flag=511;}break;case:{words[j]=ch;，；words[j+1]=\y flag=512;；break}case#{]=；words ch；words[j+l]=\0；flag=513break;case@:{；words[j]=flag=0break;default{一；；flag=1breakreturn flag;main{；i=0printf^please inputa programend with@;doch=getchar;program[i++]=ch;；}while ch!=@i=0;do{；flag=Scanprogramif flag==200{，printf%2d,%4d”flag,number;else ifflag==-1printfH%d,error%flag;，else printff%2d,%4s”flag,words;}while flag!=0;；}system pause”修改后源代码#includeHstdioh#include”stdlib h・#includestring h”intij,k,flag,number status;5；/*status whichis useto judgethe stringis keywordsor not!7char ch={}；char words

[10]；char program

[500]int Scancharprogram[]『，char*keywords

[15]=voidJmain“if,，，“then break”JintJcharJfloatTinclude”JfdrJwhile“printFJscanf,define”,“double};number=0;status=0;；j=0；ch=program[i++]/*To handlethe lettlespace andstab*//*handle letters*/〈=N ifch=2chwhile ch=ach=z；words[j++]=chch=program[i++];words[j++]=\0;；fork=0;k15k++if strempwords,keywords[k]==0switch kcase0{；flag=1；status=1break;case1{；flag=2status=1;；break}case2{flag=3;status=1;break;case3{；flag=4status=1;break;}case4{flag=5;status=1;；break}case5:{；flag=6status=1;break;}case6:{flag=7;status=1;；break；；}case7:{flag=8status=1;breakcase8:{flag=9;status=1;break;；}case9:{flag=10;status=1;break；case10:{flag=11status=1;break;；；case11:{flag=12status=1break;}；；case12{flag=13status=1break;}；；case13{flag=14status=1;break case14{flag=15;status=1;break;}if status==0；flag=100/*handle digits*/〉=〈=else if ch ch9number=0;〉〈=while ch=V ch9number=number*10+ch-O;；ch=program[i++]flag=200;■I——;}{fopereation andedge handle*/else switchch case{if ch===words[j++]=ch;，wordsfj]=\T;ch=program[i++];一if ch——；；words[j++]=ch words[j]=\0；flag=401；}else flag=402break;〉，{case，＞，if ch==words[j++]=ch;；words[j]=\0；ch=program[i++]if ch==-0；words[j++]=ch words[j]=\0;flag=403;else flag=404;break;}〈{，〈，；；；case*ifch==words[j++]=ch words[j]=0ch=program[i++]if ch==；；words[j++]=ch words[j]=\0；flag=405else flag=406;break;case!{「；；if ch==words[j++]=ch words[j]=\0ch=program[i++];if ch==；；；words[j++]=ch words[j]=*\0*flag=407；}else flag=408；}breakcase+:{；；if ch==+words[j++]=ch words[j]=\0’;ch=program[i++]if ch===words[j++]=ch;；words[j]=\0flag=409;else if ch=+words[j++]=ch;words[j]=\0’;flag=410;else flag=411;；breakcase-{if ch==-；words[j++]=chwords[j]=ch=program[i++];if ch==words[j++]=ch;；words[j]=\0flag=；}412else ifch==——words|j++]=ch;；words[j]=\T；flag=413else flag=414;break;}case*:{if ch==*words[j++]=ch;words[j]=\0;ch=program[i++];if ch==,=,；words[j++]=ch，；words[j]=\CT flag=415;；else flag=416；break}case7:{if ch==/words[j++]=ch;words[j]=\0;ch=；program[i++]if ch==words[j++]=ch;；words[j]=\0；flag=417}else；i—flag=418;case7{；flag=8；status=1；break}case8:{flag=9;status=1;；breakcase9:{；flag=10；status=1break;}case10{flag=11;status=1;；breakcase11:{；flag=12status=1;break;case12:{；flag=13status=1;break;}if status==0{；flag=100/*handle digits*/〈=else if ch=0ch9number=0;〉廿，〈=while ch0ch9tnumber=number*10+ch—0ch=program[i++];}flag=200;；i-fopereation andedge handle*/else switchch case{，if ch===words[j++]=ch;；；words[j]=\0ch=program[i++]if ch==-9words[j++]=ch;words[j]=*\05;；flag=401else flag=402;break;〉{case if ch==words[j++]=ch;words[j]=\0’;；ch=program[i++]if ch==={words[j++]=ch;；words[j]=O；flag=403}；}else flag=404；break case5〈:{ifch==Y words[j++]=ch;words[j]；；=\0ch=program[i++]if ch==words[j++]=ch;words[j]=AO9；flag=405；else i—；；flag=406break;case’!’{if ch==’!words[j++]=ch;words；[j]=\0ch=program[i++]if ch==-9{；；words[j++]=ch words[j]=\0flag=407;else{；i--；flag=408；breakcase+:{中；，if ch==words[j++]=ch words[j]=；\0；ch=program[i++]if ch===words[j++]=ch;，，；words[j]=\0；flag=409else ifch=+words[j++]=ch;words[j]=\0;flag=410;else；flag=411break;；case-{ifch==words[j++]=ch words[j]=*\05;，，ch=program[i++];ifch===words|j++]=ch;words[j]=\0;flag=412;，一,else iRch==；words[j++]=ch;words[j]=\0flag=413;}；else flag=414；break case***{ifch==*words[j++]=ch;；words[j]=\0ch=program[i++];ifch===words[j++]=ch;。