編譯原理實(shí)驗(yàn)(詞法分析)

PAGE2PAGE2編譯原理實(shí)驗(yàn)報(bào)告實(shí)驗(yàn)一實(shí)驗(yàn)題目：詞法分析指導(dǎo)老師：任姚鵬專業(yè)班級(jí)：計(jì)算機(jī)科學(xué)與技術(shù)系網(wǎng)絡(luò)工程方向1002班姓名：xxxx2013年4月13日實(shí)驗(yàn)類型__驗(yàn)證性__實(shí)驗(yàn)室_軟件實(shí)驗(yàn)室三__一、實(shí)驗(yàn)項(xiàng)目的目的和任務(wù)：了解和掌握詞法分析的方法，編程實(shí)現(xiàn)給定源語言程序的詞法分析器，并利用該分析器掃描源語言程序的字符串，按照給定的詞法規(guī)則，識(shí)別出單詞符號(hào)作為輸出，發(fā)現(xiàn)其中的詞法錯(cuò)誤。二、實(shí)驗(yàn)內(nèi)容：1．設(shè)計(jì)一個(gè)簡(jiǎn)單的程序設(shè)計(jì)語言（語言中有若干運(yùn)算符和分界符；有若干關(guān)健字；若干標(biāo)識(shí)符及若干常數(shù)）2．確定編譯中使用的表格、詞法分析器的輸出形式、標(biāo)識(shí)符與關(guān)鍵字的區(qū)分方法。3．把詞法分析器設(shè)計(jì)成一個(gè)獨(dú)立的過程。三、實(shí)驗(yàn)要求:1.從鍵盤上輸入源程序；2.處理各單詞，計(jì)算個(gè)單詞的值和類型；3.輸出個(gè)單詞名、單詞的值和類型。四、實(shí)驗(yàn)代碼#include<stdio.h>#include<string.h>charfile[1024];intlength=0;intindex; charkeywords[][10]={"auto","short","int","long","float", "double","char","struct","union","enum", "typedef","const","unsigned","signed","extern", "register","static","volatile","void","default", "if","else","switch","case","for", "do","while","goto","continue","break", "sizeof","return"};charlimits[]={'(',')','[',']','{','}',',',';'}; charoperators[]={'+','-','*','/','%', '>','<','&','|','^', '~','!','='}; //13intIsChar(charch) //是否是字符{ if((ch>='a'&&ch<='z')||(ch>='A'&&ch<='Z')) return1; return0;}intIsNumber(charch) { if((ch>='0'&&ch<='9')) return1; return0;}intIsKeyWord(intidx) //關(guān)鍵字和標(biāo)示符識(shí)別{ chartmp[30]; inti=0; while(IsChar(file[idx]))tmp[i++]=file[idx++]; //將單詞拷貝 tmp[i]='\0'; if(i==0) return0; for(i=0;i<32;i++) { if(0==strcmp(keywords[i],tmp)) //相等 { printf("(關(guān)鍵字%d,%s)\n",1,tmp); //打印結(jié)果,關(guān)鍵字 index=idx-1; //新的index的值 return1; } } return0;}intIsConst(intidx) { chartmp[30]; inti=0; if(IsChar(file[idx])&&(file[idx-1]=='\'')) //單個(gè)字符判斷{ if(file[idx+1]=='\'') //是單個(gè)的字符 {tmp[i++]=file[idx++]; tmp[i]='\0'; printf("(常數(shù)%d,%s)\n",3,tmp);//打印結(jié)果 index=idx-1; return1;} else {return0;}} elseif(IsNumber(file[idx])) //一串?dāng)?shù)字判斷 {while(IsNumber(file[idx])) tmp[i++]=file[idx++]; tmp[i++]=file[idx++]; tmp[i]='\0'; printf("(常數(shù)%d,%s)\n",3,tmp);//打印結(jié)果 index=idx-1; return1;} return0;}intIsWord(intidx) //是否是標(biāo)示符{ chartmp[30]; inti=0; if(IsKeyWord(idx))//是關(guān)鍵字就不做處理 return0; if(IsConst(idx)) //是常量不做處理 return0; if((file[idx]=='_')||(IsNumber(file[idx]))||(IsChar(file[idx]))) tmp[i++]=file[idx++]; if(i==0)return0; while((IsNumber(file[idx]))||(IsChar(file[idx]))) tmp[i++]=file[idx++]; //將單詞拷貝 tmp[i]='\0'; printf("(標(biāo)示符%d,%s)\n",2,tmp); //打印結(jié)果 index=idx-1; return1;}intIsOperator(intidx) //是否是運(yùn)算符 {chartmp[30]; intk=0; inti=0; for(k=0;k<13;k++){if(operators[k]==file[idx]) { tmp[i++]=file[idx]; index=idx; if((file[idx+1]=='=')|| ((file[idx]=='+')&&(file[idx+1]=='+'))|| ((file[idx]=='-')&&(file[idx+1]=='-'))) { tmp[i++]=file[++idx]; index=idx; } tmp[i]='\0'; printf("(運(yùn)算符%d,%s)\n",4,tmp); //打印結(jié)果 return1;}} return1;}intIsLimit(intidx) //限界符{ inti; for(i=0;i<8;i++) { if(limits[i]==file[idx]) { printf("(界限符%d,%c)\n",4,file[idx]); return1;}} return0;}intReadFile(char*name){ inti=0; intlength; charch; FILE*fp=fopen(name,"r"); if(fp==NULL) { printf("can'topenfile%s\n",name); return-1;} length=0; while((ch=fgetc(fp))!=EOF) file[length++]=ch; for(i=0;i<length;i++) putchar(file[i]); fclose(fp); returnlength;}intmain(){ if((length=ReadFile("TestDemo.c"))==-1) //讀取文件失敗 return-1; index=0; while(index<length) { while((file[index]=='')&&(index<length))index++; //去除空格 if(index>=length)return0; if(IsKeyWord(index)) //考查是不是關(guān)鍵字 {} elseif(IsConst(index)) {} elseif(IsWord(index)) //考查是不是符號(hào) {} elseif(IsLimit(index)) {} elseif(IsOperator(index)) {} index++; //考查下一個(gè)字符} return0;}五、運(yùn)行結(jié)果六、實(shí)驗(yàn)總結(jié)實(shí)驗(yàn)一是關(guān)于詞法分析