編譯原理_實(shí)驗(yàn)報(bào)告實(shí)驗(yàn)二__語(yǔ)法分析(算符優(yōu)先)2

1、.華北水利水電學(xué)院編譯原理實(shí)驗(yàn)報(bào)告一、 實(shí)驗(yàn)題目 ：語(yǔ)法分析 （算符優(yōu)先分析程序）（ 1）選擇最有代表性的語(yǔ)法分析方法算符優(yōu)先法；（ 2）選擇對(duì)各種常見(jiàn)程序語(yǔ)言都用的語(yǔ)法結(jié)構(gòu)，如賦值語(yǔ)句 （尤指表達(dá)式 ）作為分析對(duì)象，并且與所選語(yǔ)法分析方法要比較貼切。二、 實(shí)驗(yàn)內(nèi)容（ 1）根據(jù)給定文法 ，先求出 FirstVt 和 LastVt 集合 ，構(gòu)造算符優(yōu)先關(guān)系表 （要求算符優(yōu)先關(guān)系表輸出到屏幕或者輸出到文件 ）；（ 2）根據(jù)算法和優(yōu)先關(guān)系表分析給定表達(dá)式是否是該文法識(shí)別的正確的算術(shù)表達(dá)式（要求輸出歸約過(guò)程 ）（ 3）給定表達(dá)式文法為 ：G(E): E#E# EE+T | TT T*F |FF(E)|

2、i(4) 分析的句子為 : (i+i)*i 和 i+i)*i三、程序源代#include<stdlib.h>#include<stdio.h>#include<string.h>#include<iostream.h>專(zhuān)業(yè) .專(zhuān)注.#define SIZE 128char priority66;/ 算符優(yōu)先關(guān)系表數(shù)組char inputSIZE;/ 存放輸入的要進(jìn)行分析的句子char remainSIZE;/ 存放剩余串char AnalyseStackSIZE;/ 分析棧void analyse();inttestchar(char x);/

3、判斷字符X 在算符優(yōu)先關(guān)系表中的位置void remainString();/ 移進(jìn)時(shí)處理剩余字符串，即去掉剩余字符串第一個(gè)字符int k;void init()/構(gòu)造算符優(yōu)先關(guān)系表，并將其存入數(shù)組中priority00='>'priority01='<'priority02='<'priority03='<'priority04='>'priority05='>'priority10='>'priority11='>'

4、priority12='<'priority13='<'priority14='>'專(zhuān)業(yè) .專(zhuān)注.priority15='>'priority20='>'priority21='>'priority22='$'/無(wú)優(yōu)先關(guān)系的用$表示priority23='$'priority24='>'priority25='>'priority30='<'priority31=&#

5、39;<'priority32='<'priority33='<'priority34='='priority35='$'priority40='>'priority41='>'priority42='$'priority43='$'priority44='>'priority45='>'專(zhuān)業(yè) .專(zhuān)注.priority50='<'priority51='&l

6、t;'priority52='<'priority53='<'priority54='$'priority55='='void analyse()/對(duì)所輸入的句子進(jìn)行算符優(yōu)先分析過(guò)程的函數(shù)FILE *fp;fp=fopen("li","a");int i,j,f,z,z1,n,n1,z2,n2;int count=0;/操作的步驟數(shù)char a; /用于存放正在分析的字符char p,Q,p1,p2;f=strlen(input);/ 測(cè)出數(shù)組的長(zhǎng)度f(wàn)or(i=0;i&l

7、t;=f;i+)a=inputi;if(i=0)remainString();專(zhuān)業(yè) .專(zhuān)注.if(AnalyseStackk='+'|AnalyseStackk='*'|AnalyseStackk='i'|AnalyseStackk='('|AnalyseStackk=')'|AnalyseStackk='#')j=k;elsej=k-1;z=testchar(AnalyseStackj);/ 從優(yōu)先關(guān)系表中查出s j和 a 的優(yōu)先關(guān)系if(a='+'|a='*'|a

8、='i'|a='('|a=')'|a='#')n=testchar(a);else / 如果句子含有不是終結(jié)符集合里的其它字符，不合法printf(" 錯(cuò)誤 ！該句子不是該文法的合法句子！n");break;p=priorityzn;if(p='$')printf(" 錯(cuò)誤 ！該句子不是該文法的合法句子！n");return;if(p='>') for( ; ; )專(zhuān)業(yè) .專(zhuān)注.Q=AnalyseStackj;if(AnalyseStackj-1=

9、9;+'|AnalyseStackj-1='*'|AnalyseStackj-1='i'|AnalyseStackj-1='('|AnalyseStackj-1=')'|AnalyseStackj-1='#')j=j-1;elsej=j-2;z1=testchar(AnalyseStackj);n1=testchar(Q);p1=priorityz1n1;if(p1='<')/ 把 AnalyseStack j+1AnalyseStackk歸約為 Ncount+;printf(&quo

10、t;(%d)%st%10ct%5c%17st歸約n",count,AnalyseStack,p,a,remain);fprintf(fp,"(%d)%st%17st%sn",count,AnalyseStack,remain,"歸約 ");k=j+1;i-;AnalyseStackk='N'int r,r1;r=strlen(AnalyseStack);for(r1=k+1;r1<r;r1+)專(zhuān)業(yè) .專(zhuān)注.AnalyseStackr1='0'break;elsecontinue;elseif(p='

11、<')/ 表示移進(jìn)count+;printf("(%d)%st%10ct%5c%17st移進(jìn)n",count,AnalyseStack,p,a,remain);fprintf(fp,"(%d)%st%17st%sn",count,AnalyseStack,remain,"移進(jìn) ");k=k+1;AnalyseStackk=a;remainString();elseif(p='=')專(zhuān)業(yè) .專(zhuān)注.z2=testchar(AnalyseStackj);n2=testchar('#');p2=p

12、riorityz2n2;if(p2='=')count+;printf("(%d)%st%10ct%5c%17st接 受n",count,AnalyseStack,p,a,remain);fprintf(fp,"(%d)%st%17st%sn",count,AnalyseStack,remain,"接受 ");printf(" 該句子是該文法的合法句子。 n");fprintf(fp,"%s","該句子是該文法的合法句子。 n");break;elsecoun

13、t+;printf("(%d)%st%10ct%5c%17st移 進(jìn)n",count,AnalyseStack,p,a,remain);fprintf(fp,"(%d)%st%17st%sn",count,AnalyseStack,remain,"移進(jìn) ");k=k+1;專(zhuān)業(yè) .專(zhuān)注.AnalyseStackk=a;remainString();elseprintf(" 錯(cuò)誤 ！該句子不是該文法的合法句子！n");fprintf(fp,"%s","錯(cuò)誤！該句子不是該文法的合法句子。 n

14、");break;fclose(fp);int testchar(char x)int m;if(x='+')m=0;if(x='*')m=1;專(zhuān)業(yè) .專(zhuān)注.if(x='i')m=2;if(x='(')m=3;if(x=')')m=4;if(x='#')m=5;return m;void remainString()int i,j;i=strlen(remain);for( j=0;j<i;j+)remainj=remainj+1;remaini-1='0'void

15、main()int m,n;char s16= '+','*','i','(',')','#'專(zhuān)業(yè) .專(zhuān)注.init();printf(" 文法為 ： n");printf("(0)E'->#E#n");printf("(1)E->E+Tn");printf("(2)E->Tn");printf("(3)T->T*Fn");printf("(4)T->F

16、n");printf("(5)F->(E)n");printf("(6)F->in");FILE *fp;fp=fopen("li","w");fprintf(fp,"%s","要分析的文法為：n");fprintf(fp,"%s","(0)E'->#E#n");fprintf(fp,"%s","(1)E->E+Tn");fprintf(fp,"

17、%s","(2)E->Tn");fprintf(fp,"%s","(3)T->T*Fn");fprintf(fp,"%s","(4)T->Fn");fprintf(fp,"%s","(5)F->(E)n");fprintf(fp,"%s","(6)F->in");fprintf(fp,"%s","優(yōu)先關(guān)系表為：n");fprintf(fp

18、,"%s","+*i()#n");for(m=0;m<6;m+)專(zhuān)業(yè) .專(zhuān)注.fprintf(fp,"%c",s1m);for(n=0;n<6;n+)fprintf(fp,"%c",prioritymn);fprintf(fp,"%s","n");printf("-n");printf("算符優(yōu)先關(guān)系表 n");printf("+*i()#n");printf("+><<<

19、;>>n");printf("*>><<>>n");printf("i>>>>n");printf("(<<<<=n");printf(")>>>>n");printf("#<<<<=n");printf("-n");printf("請(qǐng)輸入要進(jìn)行分析的句子（以# 號(hào)結(jié)束輸入 ）:n");gets(input);/將輸入的字符串存到數(shù)組中fprintf(fp,"%s","需要分析的字符串為： n");fprintf(fp,"%s&