詞法分析 C語言編譯原理

#include<iostream>#include<string>usingnamespacestd;#defineN22intGJZ(stringc,stringa[N]);intZM(charc);intSZ(charc);voidoutput(stringa[N],stringb[N],stringc[N],stringd[N],stringe[N]);voidanalyse(FILE*fpin,stringa[N],stringb[N],stringc[N],stringd[N],stringe[N]);charch='';stringkey[15]={"begin","end","if","then","else","while","write","read","do","call","const","char","until","procedure","repeat"};voidmain(){charin_fn[30];FILE*fpin;stringa[N],b[N],c[N],d[N],e[N];cout<<"請輸入源文件名（包括路徑和后綴名）:";for(;;){cin>>in_fn;if((fpin=fopen(in_fn,"r"))!=NULL)break;elsecout<<"文件路徑錯誤！請輸入源文件名（包括路徑和后綴名）:";}analyse(fpin,a,b,c,d,e);fclose(fpin);output(a,b,c,d,e);}//判斷是否為關(guān)鍵字intGJZ(stringc,stringa[N]){inti;for(i=0;i<N;i++){ if(key[i].compare(c)==0){ a[i]=c; return1; }}return0;}//判斷是否為字母intZM(charc){ inti=0;if(((c<='z')&&(c>='a'))||((c<='Z')&&(c>='A'))){ return1; }elsereturn0;}//判斷是否為數(shù)字intSZ(charc){if(c>='0'&&c<='9')return1;elsereturn0;}voidanalyse(FILE*fpin,stringa[N],stringb[N],stringc[N],stringd[N],stringe[N]){stringarr=""; inti=0,j=0,k=0,t=0;while((ch=fgetc(fpin))!=EOF){ arr=""; if(ch==''||ch=='\t'||ch=='\n'){} elseif(ZM(ch)){ while(ZM(ch)||SZ(ch)){ if((ch<='Z')&&(ch>='A')) ch=ch+32; arr=arr+ch; ch=fgetc(fpin); } fseek(fpin,-1L,SEEK_CUR); if(GJZ(arr,a)){}else { b[i]=arr; i++; } } elseif(SZ(ch)){ while(SZ(ch)||ch=='.'&&SZ(fgetc(fpin))){ arr=arr+ch; ch=fgetc(fpin); } fseek(fpin,-1L,SEEK_CUR); c[j]=arr; j++; } elseswitch(ch){case'+':case'-':case'*':case'=':case'/':{e[t]=ch;t++;}break;case'(':case')':case'[':case']':case';':case'.':case',':case'{':case'}':{d[k]=ch;k++;}break;case':':{ch=fgetc(fpin); if(ch=='='){e[t]=":=";t++;} else{e[t]="=";t++;fseek(fpin,-1L,SEEK_CUR);}}break; case'>':{ch=fgetc(fpin); if(ch=='='){e[t]=">=";t++;}if(ch=='>'){e[t]=">>";t++;}else{e[t]=">";t++; fseek(fpin,-1L,SEEK_CUR);}}break;case'<':{ch=fgetc(fpin);if(ch=='='){e[t]="<=";t++;}elseif(ch=='<'){e[t]="<<";t++;}elseif(ch=='>'){e[t]="<>";t++;}else{e[t]="<";t++;fseek(fpin,-1L,SEEK_CUR);}}break;default:cout<<ch<<"\t無法識別字符"<<endl;}}}voidoutput(stringa[N],stringb[N],stringc[N],stringd[N],stringe[N]){inti;cout<<"關(guān)鍵字為："<<endl;for(i=0;i<N;i++) cout<<a[i]<<"";cout<<endl; cout<<"標(biāo)識符為："<<endl;for(i=0;i<N;i++) cout<<b[i]<<"";cout<<endl; cout<<"常數(shù)為："<<endl;for(i=0;i<N;i++) cout<<c[i]<<"";cout<<endl; cout<<"界符為："<<endl;for(i=0;i<N;i++) cout<