SAMPLE 词法分析程序 C++版

#include<fstream.h> #include<iostream.h> #include<string.h> char *word[36]={"","and","array","begin","bool","call","case", "char","constant","dim","do","else","end","false","for","if","input", "integer","not","of","or","output", "procedure","program","read", "real","repeat","set","stop","then","to","true","until","var","while","write"}; int a[10000],b[10000]; char copy[1000][1000]; char achar[1000000]; int line=1,biaoji1=1,num=1,abnum=1,charnum=1; void scan(); void zifuchuan(); void number(); void zhuxi(); void fuhao(); void zifuchangliang(); void inputfile(); void output(); bool wrong=false; void fuhao() { if(achar[num]=='.'&&achar[num+1]=='.') { a[abnum]=47; b[abnum]=0; abnum++; num+=2; } else if(achar[num]==':'&&achar[num+1]=='=') { a[abnum]=51; b[abnum]=0; abnum++; num+=2; } else if(achar[num]=='<'&&achar[num+1]=='=') { a[abnum]=54; b[abnum]=0; abnum++; num+=2; } else if(achar[num]=='<'&&achar[num+1]=='>') { a[abnum]=55; b[abnum]=0; abnum++; num+=2; } else if(achar[num]=='>'&&achar[num+1]=='=') { a[abnum]=58; b[abnum]=0; abnum++; num+=2; } else if(achar[num]=='(') { a[abnum]=39; b[abnum]=0; abnum++; num++; } else if(achar[num]==')') { a[abnum]=40; b[abnum]=0; abnum++; num++; } else if(achar[num]=='*') { a[abnum]=41; b[abnum]=0; abnum++; num++; } else if(achar[num]=='+') { a[abnum]=43; b[abnum]=0; abnum++; num++; } else if(achar[num]==',') { a[abnum]=44; b[abnum]=0; abnum++; num++; } else if(achar[num]=='-') { a[abnum]=45; b[abnum]=0; abnum++; num++; } else if(achar[num]=='.') { a[abnum]=46; b[abnum]=0; abnum++; num++; } else if(achar[num]=='/') { a[abnum]=48; b[abnum]=0; abnum++; num++; } else if(achar[num]==':') { a[abnum]=50; b[abnum]=0; abnum++; num++; } else if(achar[num]==';') { a[abnum]=52; b[abnum]=0; abnum++; num++; } else if(achar[num]=='<') { a[abnum]=53; b[abnum]=0; abnum++; num++; } else if(achar[num]=='=') { a[abnum]=56; b[abnum]=0; abnum++; num++; } else if(achar[num]=='>') { a[abnum]=57; b[abnum]=0; abnum++; num++; } else if(achar[num]=='[') { a[abnum]=59; b[abnum]=0; abnum++; num++; } else if(achar[num]==']') { a[abnum]=60; b[abnum]=0; abnum++; num++; } else { wrong=true; cout<<"Line "<<line<<":"<<"出现非法符号!"<<endl; num++; } if(num<charnum) scan(); } void inputfile() { char n[300],ch; cin>>n; ifstream infile(n); while(infile.get(ch)) achar[charnum++]=ch; } void number() { char store[1000]; store[0]=achar[num]; num++; int i=0; bool isnumber=true; while((achar[num]>='a'&&achar[num]<='z')||(achar[num]>='A'&&achar[num]<='Z')||(achar[num]>='0'&&achar[num]<='9')) { store[++i]=achar[num]; if(achar[num]<'0'||achar[num]>'9') isnumber=false; num++; } int l1=i+1; if(isnumber) a[abnum]=37; else { wrong=true; cout<<"Line "<<line<<":"<<"出现非法字符集!"<<endl; } store[l1]='\0'; for(i=1;i<biaoji1;i++) { int j=strcmp(copy[i],store); if(strcmp(copy[i],store)==0) { b[abnum]=i; abnum++; break; } } if(i==biaoji1) { b[abnum]=biaoji1; strcpy(copy[biaoji1],store); biaoji1++; abnum++; } if(num<charnum) { if(achar[num]==' ')scan(); else if(achar[num]=='\n')scan(); else if(achar[num]=='/'&&achar[num+1]=='*')num+=2,zhuxi(); else if(achar[num]=='\'')zifuchangliang(); else fuhao(); } } void output() { if(!wrong) { int i; for(i=1;i<abnum;i++) { cout<<"("<<a[i]<<","; if(b[i]) cout<<b[i]; else cout<<"-"; cout<<") "; if(i%5==0) cout<<endl; } cout<<endl; } } void scan() { while(num<charnum) { if((achar[num]>='a'&&achar[num]<='z')||(achar[num]>='A'&&achar[num]<='Z')) zifuchuan(); else if(achar[num]>='0'&&achar[num]<='9') number(); else if(achar[num]=='/') { if(achar[num+1]=='*') num+=2,zhuxi(); else fuhao(); } else if(achar[num]=='\n') line++,num++; else if(achar[num]==' ') num++; else if(achar[num]=='\'') zifuchangliang(); else fuhao(); } } void zhuxi() { while(achar[num]!='*'||achar[num+1]!='/') { if(achar[num]=='\n'||num>=charnum) { wrong=true; cout<<"Line "<<line<<":"<<"缺少右边符号'*/'!"<<endl; line++; num++; break; } num++; } if(achar[num]=='*'||achar[num+1]=='/') num+=2; if(num<charnum) scan(); } void zifuchuan() { char store[1000]; store[0]=achar[num]; num++; int i=1; while((achar[num]>='a'&&achar[num]<='z')||(achar[num]>='A'&&achar[num]<='Z')||(achar[num]>='0'&&achar[num]<='9')) store[i++]=achar[num++]; int l1=i; store[l1]='\0'; for(i=1;i<=35;i++) { if(strcmp(word[i],store)==0) { a[abnum]=i; b[abnum]=0; abnum++; break; } } if(i==36) { for(i=1;i<biaoji1;i++) { if(strcmp(copy[i],store)==0) { a[abnum]=36; b[abnum]=i; abnum++; break; } } if(i==biaoji1) { a[abnum]=36; b[abnum]=biaoji1; abnum++; strcpy(copy[biaoji1],store); biaoji1++; } } if(num<charnum) { if(achar[num]==' ')scan(); else if(achar[num]=='\n')scan(); else if(achar[num]=='/'&&achar[num+1]=='*')num=+2,zhuxi(); else if(achar[num]=='\'')zifuchangliang(); else fuhao(); } } void zifuchangliang() { char store[1000]; store[0]=achar[num]; int i=0; num++; while(achar[num]!='\'') { if(achar[num]=='\n'||num>=charnum) { wrong=true; cout<<"Line "<<line<<":"<<"缺少右边单引号!"<<endl; line++; break; } store[++i]=achar[num]; num++; } int l1=i+1; store[l1]='\0'; num++; for(i=1;i<biaoji1;i++) { if(strcmp(copy[i],store)==0) { a[abnum]=38; b[abnum]=i; abnum++; break; } } if(i==biaoji1) { a[abnum]=38; b[abnum]=biaoji1; abnum++; strcpy(copy[biaoji1],store); biaoji1++; } if(num<charnum) { if(achar[num]==' ')scan(); else if((achar[num]>='a'&&achar[num]<='z')||(achar[num]>='A'&&achar[num]<='Z'))zifuchuan(); else if(achar[num]>='0'&&achar[num]<='9')number(); else if(achar[num]=='\n')scan(); else if(achar[num]=='/'&&achar[num+1]=='*')num=+2,zhuxi(); else if(achar[num]=='\'')zifuchangliang(); else fuhao(); } } int main() { cout<<endl<<endl<<endl; cout<<"杨超"<<endl; cout<<"200930583011"<<endl; cout<<"计科2"<<endl; cout<<endl<<endl; cout<<"输入文件路径:"; inputfile(); scan(); output(); return 0; }