語法分析 實驗報告

編譯原理實驗報告實驗名稱： 語法分析 實驗類型： 設計性實驗 指導教師： 蔣勇 專業(yè)班級： 軟件1001班 姓名：李岳東 學號：20101557實驗地點：東6A-319實驗成績：____________________________日期：2012年月日一、實驗目的編譯技術是理論與實踐并重的課程，而其實驗課要綜合運用一、二年級所學的多門課程的內容，用來完成一個小型編譯程序。從而鞏固和加強對詞法分析、語法分析、語義分析、代碼生成和報錯處理等理論的認識和理解；培養(yǎng)學生對完整系統(tǒng)的獨立分析和設計的能力，進一步培養(yǎng)學生的獨立編程能力。二、實驗設計三、實驗過程1)給定文法：（文法舉例） EE+T｜T TT*F｜F F(E)｜i2)構造FIRST()集和FOLLOW()集表3-1FIRST()集和FOLLOW()集FIRSTFOLLOWE(，i#,+,)T(，i#,+,),*F(，i#,+,),* 四、實驗結果 表4-1分析成功 表4-2分析失敗 表4-3載入文件出錯 流程圖如下所示：五、附錄：關鍵代碼#include<iostream>#include<stdio.h>#include<ctype.h>#include<conio.h>#include<string.h>usingnamespacestd;intTESTparse();intprogram();intcompound_Stat();intstatement();intexpression_Stat();intexpression_r();intbool_expr();intadditive_expr();intterm();intfactor();intif_stat();intwhile_stat();intfor_stat();intwrite_stat();intread_stat();intdeclaration_stat();intdeclaration_list();intstatement_list();intcompound_stat();chartoken[20],token1[40];//token保存單詞符號，token1保存單詞值charScanout[300];//保存詞法分析輸出文件名FILE*fp;//用于指向輸入輸出文件的指針//語法分析程序intTESTparse(){intes=0;if((fp=fopen(Scanout,"r"))==NULL){printf("\n打開%s錯誤!\n",Scanout);es=10;}if(es==0)es=program();printf("=====語法分析結果!======\n");switch(es){case0:printf("語法分析成功!\n");break;case10:printf("打開文件%s失敗!\n",Scanout);break;case1:printf("缺少{!\n");break;case2:printf("缺少}!\n");break;case3:printf("缺少標識符!\n");break;case4:printf("少分號!\n");break;case5:printf("缺少(!\n");break;case6:printf("缺少)!\n");break;case7:printf("缺少操作數(shù)!\n");break;}fclose(fp);return(es);}//<程序>::={<聲明序列><語句序列>}//program::={<declaration_list><statement_list>}intprogram(){intes=0;fscanf(fp,"%s%s\n",token,token1);printf("%s%s\n",token,token1);if(strcmp(token,"{"))//判斷是否'{'{es=1;return(es);}fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);es=declaration_list();if(es>0)return(es);es=statement_list();if(es>0)return(es);if(strcmp(token,"}"))//判斷是否'}'{es=2;return(es);}return(es);}//<聲明序列>::=<聲明序列><聲明語句>|<聲明語句>//<declaration_list>::=//<declaration_list><declaration_stat>|<declaration_stat>//該成<declaration_list>::={<declaration_stat>}intdeclaration_list(){intes=0;while(strcmp(token,"int")==0){es=declaration_stat();if(es>0)return(es);}return(es);}//<聲明語句>::=int<變量>；//<declaration_stat>::=intID;intdeclaration_stat(){intes=0;fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);if(strcmp(token,"ID"))return(es=3);//不是標識符fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);if(strcmp(token,";"))return(es=4);fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);return(es);}//<語句序列>::=<語句序列><語句>|<語句>//<statement_list>::=<statement_list><statement>|<statement>//改成<statement_list>::={<statement>}intstatement_list(){intes=0;while(strcmp(token,"}")){es=statement();if(es>0)return(es);}return(es);}//<語句>::=<if語句>|<while語句>|<for語句>|<read語句>//|<write語句>|<復合語句>|<表達式語句>//<statement>::=<if_stat>|<while_stat>|<for_stat>//|<compound_stat>|<expression_stat>intstatement(){intes=0;if(es==0&&strcmp(token,"if")==0)es=if_stat();//<IF語句>if(es==0&&strcmp(token,"while")==0)es=while_stat();//<while語句>if(es==0&&strcmp(token,"for")==0)es=for_stat();//<for語句>//可在此處添加do語句調用if(es==0&&strcmp(token,"read")==0)es=read_stat();//<read語句>if(es==0&&strcmp(token,"write")==0)es=write_stat();//<write語句>if(es==0&&strcmp(token,"{")==0)es=compound_stat();//<復合語句>if(es==0&&(strcmp(token,"ID")==0||strcmp(token,"NUM")==0||strcmp(token,"(")==0))es=expression_Stat();//<表達式語句>return(es);}//<IF語句>::=if(<表達式>)<語句>[else<語句>]//<IF_stat>::=if(<expr>)<statement>[else<statement>]intif_stat(){intes=0;//iffscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);if(strcmp(token,"("))return(es=5);//少左括號fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);es=expression_r();if(es>0)return(es);if(strcmp(token,")"))return(es=6);//少右括號fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);es=statement();if(es>0)return(es);if(strcmp(token,"else")==0)//else部分處理{fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);es=statement();if(es>0)return(es);}return(es);}//<while語句>::=while(<表達式>)<語句>//<while_stat>::=while(<expr>)<statement>intwhile_stat(){intes=0;fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);if(strcmp(token,"("))return(es=5);//少左括號fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);es=expression_r();if(es>0)return(es);if(strcmp(token,")"))return(es=6);//少右括號fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);es=statement();return(es);}//<for語句>::=for(<表達式>;<表達式>;<表達式>)<語句>//<for_stat>::=for(<expr>,<expr>,<expr>)<statement>intfor_stat(){intes=0;fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);if(strcmp(token,"("))return(es=5);//少左括號fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);es=expression_r();if(es>0)return(es);if(strcmp(token,";"))return(es=4);//少分號fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);es=expression_r();if(es>0)return(es);if(strcmp(token,";"))return(es=4);//少分號fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);es=expression_r();if(es>0)return(es);if(strcmp(token,")"))return(es=6);//少右括號fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);es=statement();return(es);}//<write_語句>::=write<表達式>;//<write_stat>::=write<expression>;intwrite_stat(){intes=0;fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);es=expression_r();if(es>0)return(es);if(strcmp(token,";"))return(es=4);//少分號fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);return(es);}//<read_語句>::=read<變量>;//<read_stat>::=readID;intread_stat(){intes=0;fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);if(strcmp(token,"ID"))return(es=3);//少標識符fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);if(strcmp(token,";"))return(es=4);//少分號fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);return(es);}//<復合語句>::={<語句序列>}//<compound_stat>::={<statement_list>}intcompound_stat(){//復合語句函數(shù)intes=0;fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);es=statement_list();return(es);}//<表達式語句>::=<<表達式>;|;//<expression_stat>::=<expression>;|;intexpression_stat(){intes=0;if(strcmp(token,";")==0){fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);return(es);}es=expression_r();if(es>0)return(es);if(es==0&&strcmp(token,";")==0){fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);return(es);}else{es=4;return(es);//少分號}}//<表達式>::=<標識符>=<布爾表達式>|<布爾表達式>//<expr>::=ID=<bool_expr>|<bool_expr>intexpression_r(){intes=0,fileadd;chartoken2[20],token3[40];printf("aaaaaaaaaaa%s\n",token);if(strcmp(token,"ID")==0){fileadd=ftell(fp);//記住當前文件位置fscanf(fp,"%s%s\n",&token2,&token3);printf("%s%s\n",token2,token3);if(es>0)return(es);if(strcmp(token2,"=")==0)//'='{fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);es=bool_expr();}else{fseek(fp,fileadd,0);//若非'='則文件指針回到'='前的標識符printf("%s%s\n",token,token1);es=bool_expr();if(es>0)return(es);}}elsees=bool_expr();return(es);}//<布爾表達式>::=<算術表達式>|<算術表達式>(>|<|>=|<=|==|!=)<算術表達式>//<bool_expr>::=<additive_expr>//|<additive_expr>(>|<|>=|<=|==|!=)<additive_expr>intbool_expr(){intes=0;es=additive_expr();if(es>0)return(es);if(strcmp(token,">")==0||strcmp(token,">=")==0||strcmp(token,"<")==0||strcmp(token,"<=")==0||strcmp(token,"==")==0||strcmp(token,"!=")==0){fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);es=additive_expr();if(es>0)return(es);}return(es);}//<算術表達式>::=<項>{(+|-)<項>}//<additive_expr>::=<term>{(+|-)<term>}intadditive_expr(){intes=0;es=term();if(es>0)return(es);while(strcmp(token,"+")==0||strcmp(token,"-")==0){fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);es=term();if(es>0)return(es);}return(es);}//<項>::=<因子>{(*|/)<因子>}//<term>::=<factor>{(*|/)<factor>}intterm(){intes=0;es=factor();if(es>0)return(es);while(strcmp(token,"*")==0||strcmp(token,"/")==0){fscanf(fp,"%s%s\n",&token,&token1);printf("%s%s\n",token,token1);es=factor();if(es>0