IF-ELSE条件语句的翻译程序设计(简单优先法、输出四元式)

#includefstream#includeiostream#includestring#includeiomanip#includecmath#includestdio.h#includestdlib.h#includeassert.husingnamespacestd;#defineSTACK_INIT_SIZE50#defineSTACKINCREMENT30#defineOK1#defineERROR-1#defineFAILURE-1///////////////////////////////////////*(1)S-ifEthenBelseB(2)E-(AA)(3)E-(AA)(4)E-(A)(5)A-d(6)A-num(7)B-{d=C}(8)C-A+A(9)C-A-A(10)C-A*A(11)C-A/A(12)C-A*////////////////////////////////////////intlineno=1;charch;intanltable[22][22]={/*S*/{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2},/*if*/{0,0,3,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},/*E*/{0,0,0,3,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},/*then*/{0,0,0,0,3,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0},/*B*/{0,0,0,0,0,3,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2},/*else*/{0,0,0,0,3,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0},/*(*/{0,0,0,0,0,0,0,0,0,0,0,3,1,1,0,0,0,0,0,0,0,0},/*)*/{0,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},/**/{0,0,0,0,0,0,0,0,0,0,0,3,1,1,0,0,0,0,0,0,0,0},/**/{0,0,0,0,0,0,0,0,0,0,0,3,1,1,0,0,0,0,0,0,0,0},/*=*/{0,0,0,0,0,0,0,0,0,0,0,1,1,1,3,0,0,0,0,0,0,0},/*A*/{0,0,0,0,0,0,0,3,3,3,0,0,0,0,0,0,2,3,3,3,3,0},/*d*/{0,0,0,0,0,0,0,2,2,2,3,0,0,0,0,0,2,2,2,2,2,0},/*num*/{0,0,0,0,0,0,0,2,2,2,0,0,0,0,0,0,2,2,2,2,2,0},/*C*/{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,0},/*{*/{0,0,0,0,0,0,0,0,0,0,0,0,3,0,0,0,0,0,0,0,0,0},/*}*/{0,0,0,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2},/*+*/{0,0,0,0,0,0,0,0,0,0,0,3,1,1,0,0,0,0,0,0,0,0},/*_*/{0,0,0,0,0,0,0,0,0,0,0,3,1,1,0,0,0,0,0,0,0,0},/***/{0,0,0,0,0,0,0,0,0,0,0,3,1,1,0,0,0,0,0,0,0,0},/*/*/{0,0,0,0,0,0,0,0,0,0,0,3,1,1,0,0,0,0,0,0,0,0},/*#*/{1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0},};//0-error,1=,2=,3==charallname[30][30];//单词全名charout[30][30];//保存单词简称intlength;structatt{//名字表类型stringsname;charselect;charaddre;};attattname[40];//名字表typedefstructSqStack{char*base;char*top;intstacksize;}SqStack;//栈定义voidInitStack(SqStack&S){//栈初始化S.base=(char*)malloc(STACK_INIT_SIZE*sizeof(char));//分配存储空间if(!S.base)exit(OVERFLOW);//为栈S分配存储空间失败S.top=S.base;S.stacksize=STACK_INIT_SIZE;}intpush(SqStack&S,charch)//将元素e插入到栈S中，成为新的栈顶元素{if(S.top-S.baseS.stacksize)//判定栈是否满{S.base=(char*)realloc(S.base,(S.stacksize+STACKINCREMENT*sizeof(char)));if(!S.base){printf(分配存储单元失败.\n);//存储单元分配失败exit(OVERFLOW);}S.top=S.base+S.stacksize;//指明栈顶指针的基址S.stacksize+=STACKINCREMENT;//指明栈的空间大小}//endofif*S.top++=ch;//先将e送入栈顶指针所指向的单元，再将栈顶指针加1return(OK);}//endofPush()subfunctionintpop(SqStack&S,char&ch){//栈顶元素出栈if(S.top==S.base){printf(溢出);return(ERROR);}ch=*--S.top;return(OK);}chargettop(SqStackS){//返回栈顶元素if(S.top==S.base)cout栈空，出错endl;chare;e=*(S.top-1);returne;}intgetnum(charcc){//返回元素在优先表中的位置switch(cc){case'S':return0;break;case'i':return1;break;case'E':return2;break;case't':return3;break;case'B':return4;break;case'e':return5;break;case'(':return6;break;case')':return7;break;case'':return8;break;case'':return9;break;case'=':return10;break;case'A':return11;break;case'd':return12;break;case'n':return13;break;case'C':return14;break;case'{':return15;break;case'}':return16;break;case'+':return17;break;case'-':return18;break;case'*':return19;break;case'/':return20;break;case'#':return21;break;default:return88;}}intjudge(char*string){//判断是否是关键字char*keywords[1000]={if,then,else};for(inti=0;i=2;i++){if(!strcmp(string,*(keywords+i))){return1;}}return0;}intanalysis(ifstream&fin,ofstream&fout)//词法分析程序,用引用传递参数{chartemp[10];//临时存放已读入但无法判断类型的字符intj=0;intou=0;intna=0;while(fin.get(ch)){if(ch=='\n'){lineno+=1;}elseif(ch=='\t'||ch==''){}//排除制表、空格字符elseif(isalpha(ch))//当前输入符为字母{while(isalpha(ch)||isdigit(ch)){temp[j]=ch;j++;fin.get(ch);}temp[j]='\0';//标志字符串结束j=0;if(judge(temp))//判断是否为关键字{memcpy(allname[na],temp,10);attname[na].sname=allname[na];attname[na].select=allname[na][0];memcpy(out[ou],temp,10);ou++;fout(attname[na].sname,关键字)endl;na++;}else{memcpy(allname[na],temp,10);attname[na].sname=allname[na];attname[na].select='d';memcpy(out[ou],temp,10);ou++;fout(attname[na].sname,变量)endl;na++;}fin.seekg(-1,ios::cur);//回退1个字符}elseif(isdigit(ch)){while(isdigit(ch)){temp[j]=ch;j++;fin.get(ch);}temp[j]='\0';//标志字符串结束j=0;memcpy(allname[na],temp,10);attname[na].sname=allname[na];attname[na].select='n';memcpy(out[ou],temp,10);ou++;fout(attname[na].sname,常量)endl;na++;fin.seekg(-1,ios::cur);//回退一个字符}elseif(ch=='='){allname[na][0]=ch;attname[na].sname=allname[na];attname[na].select=ch;memcpy(out[ou],=,10);ou++;fout(attname[na].sname,算符)endl;na++;}elseif(ch=='+'){allname[na][0]=ch;attname[na].sname=allname[na];attname[na].select=ch;memcpy(out[ou],+,10);ou++;fout(attname[na].sname,算符)endl;na++;}elseif(ch=='-'){allname[na][0]=ch;attname[na].sname=allname[na];attname[na].select=ch;memcpy(out[ou],-,10);ou++;fout(attname[na].sname,算符)endl;na++;}elseif(ch=='*'){allname[na][0]=ch;attname[na].sname=allname[na];attname[na].select=ch;memcpy(out[ou],*,10);ou++;fout(attname[na].sname,算符)endl;na++;}elseif(ch=='/'){allname[na][0]=ch;attname[na].sname=allname[na];attname[na].select=ch;memcpy(out[ou],/,10);ou++;fout(attnam