實驗二編譯原理語法分析算符優(yōu)先

1、實驗二 語法分析算符優(yōu)先分析程序一實驗要求 選擇最有代表性的語法分析方法算符優(yōu)先法； 選擇對各種常見程序語言都用的語法結構，如賦值語句（尤指表達式）作為分析對象，并且與所選語法分析方法要比較貼切。 實習時間為6學時。二實驗內容及要求（1）根據給定文法，先求出FirstVt和LastVt集合，構造算符優(yōu)先關系表（要求算符優(yōu)先關系表 輸出到屏幕或者輸出到文件）；（2）根據算法和優(yōu)先關系表分析給定表達式是否是該文法識別的正確的算術表達式（要求輸出歸約過程）（3）給定表達式文法為： G(E): E#E#EE+T | TTT*F |FF(E)|i(4)分析的句子為: (i+i)*i和i+i)*i三.實驗

2、代碼#include "stdafx.h"#include "stdio.h"#include "stdlib.h"#include "iostream.h"int k; char a; int j; char q; int r; int r1; char st1030; char data2020; char s100; char lable20; char input100; char string2010; char first1010; char last1010; int fflag10=0; int l

3、flag10=0; int deal(); int zhongjie(char c); int xiabiao(char c); void out(int j,int k,char *s); void firstvt(char c); void lastvt(char c); void table(); void main()int i,j,k=0; printf("請輸入文法規(guī)則數：");scanf("%d",&r);printf("請輸入文法規(guī)則：n");for(i=0;i<r;i+)scanf("%s&q

4、uot;,sti); firsti0=0; lasti0=0;for(i=0;i<r;i+) for(j=0;stij!='0'j+)if(sti0<'A'|sti0>'Z')printf("不是算符文法!n"); exit(-1);if(stij>='A'&&stij<='Z') if(stij+1>='A'&&stij+1<='Z')printf("不是算符文法!n"

5、); exit(-1); for(i=0;i<r;i+)for(j=0;stij!='0'j+)if(stij<'A'|stij>'Z')&&stij!='-'&&stij!='>'&&stij!='|')lablek+=stij;lablek='#'lablek+1='0' table(); /輸出每個非終結符的FIRSTVT集printf("每個非終結符的FIRSTVT集為：n&qu

6、ot;); for(i=0;i<r;i+)printf("%c: ",sti0);for(j=0;j<firsti0;j+)printf("%c ",firstij+1);printf("n");/輸出每個非終結符的LASTVT集printf("每個非終結符的LASTVT集為：n"); for(i=0;i<r;i+)printf("%c: ",sti0);for(j=0;j<lasti0;j+)printf("%c ",lastij+1);printf

7、("n");printf("算符優(yōu)先分析表如下:n");for(i=0;lablei!='0'i+) printf("t%c",lablei);printf("n"); for(i=0;i<k+1;i+)printf("%ct",lablei);for(j=0;j<k+1;j+)printf("%ct",dataij);printf("n");printf("請輸入文法輸入符號串以#結束:");scanf(&

8、quot;%s",input); deal();void table()char text2010;int i,j,k,t,l,x=0,y=0;int m,n;x=0;for(i=0;i<r;i+)firstvt(sti0);lastvt(sti0);for(i=0;i<r;i+)textxy=sti0;y+;for(j=1;stij!='0'j+)if(stij='|')textxy='0'x+;y=0;textxy=sti0;y+;textxy+='-'textxy+='>'else

9、textxy=stij;y+;textxy='0'x+;y=0;r1=x; /輸出轉化后的文法規(guī)則串printf("轉化后的文法為:n");for(i=0;i<x;i+) printf("%sn",texti);for(i=0;i<x;i+) stringi0=texti0;for(j=3,l=1;textij!='0'j+,l+)stringil=textij;stringil='0'for(i=0;i<x;i+)for(j=1;textij+1!='0'j+)if(zh

10、ongjie(textij)&&zhongjie(textij+1)m=xiabiao(textij);n=xiabiao(textij+1);datamn='='if(textij+2!='0'&&zhongjie(textij)&&zhongjie(textij+2)&&!zhongjie(textij+1)m=xiabiao(textij);n=xiabiao(textij+2);datamn='='if(zhongjie(textij)&&!zhongjie(

11、textij+1)for(k=0;k<r;k+)if(stk0=textij+1)break;m=xiabiao(textij);for(t=0;t<firstk0;t+)n=xiabiao(firstkt+1);datamn='<'if(!zhongjie(textij)&&zhongjie(textij+1)for(k=0;k<r;k+)if(stk0=textij)break;n=xiabiao(textij+1);for(t=0;t<lastk0;t+)m=xiabiao(lastkt+1);datamn='>

12、'm=xiabiao('#');for(t=0;t<first00;t+)n=xiabiao(first0t+1);datamn='<'n=xiabiao('#');for(t=0;t<last00;t+)m=xiabiao(last0t+1);datamn='>'datann='=' /求FIRSTVT集void firstvt(char c) int i,j,k,m,n;for(i=0;i<r;i+)if(sti0=c)break;if(fflagi=0)n=firsti0

13、+1;m=0;doif(m=2|stim='|')if(zhongjie(stim+1)firstin=stim+1;n+;elseif(zhongjie(stim+2)firstin=stim+2;n+;if(stim+1!=c)firstvt(stim+1);for(j=0;j<r;j+)if(stj0=stim+1)break;for(k=0;k<firstj0;k+)int t;for(t=0;t<n;t+)if(firstit=firstjk+1)break;if(t=n)firstin=firstjk+1;n+;m+;while(stim!=

14、9;0');firstin='0'firsti0=-n;fflagi=1; /求LASTVT集void lastvt(char c) int i,j,k,m,n;for(i=0;i<r;i+)if(sti0=c)break;if(lflagi=0)n=lasti0+1;m=0;doif(stim+1='0'|stim+1='|')if(zhongjie(stim)lastin=stim;n+;elseif(zhongjie(stim-1)lastin=stim-1;n+;if(stim!=c)lastvt(stim);for(j=0

15、;j<r;j+)if(stj0=stim)break;for(k=0;k<lastj0;k+)int t;for(t=0;t<n;t+)if(lastit=lastjk+1)break;if(t=n)lastin=lastjk+1;n+;m+;while(stim!='0');lastin='0'lasti0=-n;lflagi=1;int deal()int i,j;int x,y;int z; k=1;sk='#' for(i=0;inputi!='0'i+); z=i-;i=0;while(a=inputi

16、)!='0')if(zhongjie(sk)j=k;elsej=k-1;x=xiabiao(sj);y=xiabiao(a);if(dataxy='>')out(1,k,s);printf("%c",a);out(i+1,z,input);printf("規(guī)約n");doq=sj;if(zhongjie(sj-1)j=j-1;else j=j-2;x=xiabiao(sj);y=xiabiao(q);while(dataxy!='<');int m,n,N;for(m=j+1;m<=k;m

17、+)for(N=0;N<r1;N+)for(n=1;stringNn!='0'n+)if(!zhongjie(sm)&&!zhongjie(stringNn)if(zhongjie(sm+1)&&zhongjie(stringNn+1)&&sm+1=stringNn+1)sj+1=stringN0; break; elseif(zhongjie(sm)if(sm=stringNn)sj+1=stringN0; break; k=j+1;if(k=2&&a='#')out(1,k,s);prin

18、tf("%c",a);out(i+1,z,input);printf("結束n");printf("輸入串符合文法的定義！n");return 1; elseif(dataxy='<'|dataxy='=') out(1,k,s);printf("%c",a);out(i+1,z,input);printf("移進n");k+;sk=a;i+;elseprintf("nflase");return 0;printf("nflase");return 0;void out(int j,int k,char *s)int n=0;int i;for(i=j;i<=k;i+)printf("%c",si);n+;for(;n<15;n+)printf(" ");/判斷字符c是否是終極符int zhongjie(char c) int i;for(i=0;l