LL语法分析程序设计

1、#include stdio.h#include stdlib.h#define MaxRuleNum 8#define MaxVnNum 5#define MaxVtNum 5#define MaxStackDepth 20#define MaxPLength 20#define MaxStLength 50struct pRNode /*产生式右部结构*/ int rCursor; /*右部序号*/ struct pRNode *next;struct pNode /*产生式结点结构*/ int lCursor; /*左部符号序号*/ int rLength; /*右部长度*/ /*注当r

2、Length = 1 时，rCursor = -1为空产生式*/ struct pRNode *rHead; /*右部结点头指针*/;char VnMaxVnNum + 1; /*非终结符集*/int vnNum;char VtMaxVtNum + 1; /*终结符集*/int vtNum;struct pNode PMaxRuleNum; /*产生式*/int PNum; /*产生式实际个数*/char bufferMaxPLength + 1;char ch; /*符号或string ch;*/char stMaxStLength; /*要分析的符号串*/struct collectNod

3、e /*集合元素结点结构*/ int nVt; /*在终结符集中的下标*/ struct collectNode *next;struct collectNode* firstMaxVnNum + 1; /*first集*/struct collectNode* followMaxVnNum + 1; /*follow集*/int analyseTableMaxVnNum + 1MaxVtNum + 1 + 1;/*预测分析表存放为产生式的编号，+1用于存放结束符，多+1用于存放#(-1)*/int analyseStackMaxStackDepth + 1; /*分析栈*/int topAn

4、alyse; /*分析栈顶*/*int reverseStackMaxStackDepth + 1; /*颠倒顺序栈*/*int topReverse; /*倒叙栈顶*/void Init();/*初始化*/int IndexCh(char ch);/*返回Vn在Vn表中的位置+100、Vt在Vt表中的位置，-1表示未找到*/void InputVt(); /*输入终结符*/void InputVn();/*输入非终结符*/void ShowChArray(char* collect, int num);/*输出Vn或Vt的内容*/void InputP();/*产生式输入*/bool Che

5、ckP(char * st);/*判断产生式正确性*/void First(int U);/*计算first集,U-xx.*/void AddFirst(int U, int nCh); /*加入first集*/bool HaveEmpty(int nVn); /*判断first集中是否有空(-1)*/void Follow(int V);/*计算follow集*/void AddFollow(int V, int nCh, int kind);/*加入follow集， kind = 0表加入follow集，kind = 1加入first集*/void ShowCollect(struct c

6、ollectNode *collect);/*输出first或follow集*/void FirstFollow();/*计算first和follow*/void CreateAT();/*构造预测分析表*/void ShowAT();/*输出分析表*/void Identify(char *st);/*主控程序,为操作方便*/*分析过程显示操作为本行变换所用，与教程的显示方式不同*/void InitStack();/*初始化栈及符号串*/void ShowStack();/*显示符号栈中内容*/void Pop();/*栈顶出栈*/void Push(int r);/*使用产生式入栈操作*

7、/#include LL1.hvoid main() char todo,ch; void Init(); InputVn(); InputVt(); InputP(); getchar(); FirstFollow(); printf(所得first集为：); ShowCollect(first); printf(所得follow集为：); ShowCollect(follow); CreateAT(); ShowAT(); todo = y; while(y = todo) printf(n是否继续进行句型分析？(y / n):); todo = getchar(); while(y !=

8、 todo & n != todo) printf(n(y / n)? ); todo = getchar(); if(y = todo) int i; InitStack(); printf(请输入符号串(以#结束) : ); ch = getchar(); i = 0; while(# != ch & i MaxStLength) if( != ch & n != ch) sti+ = ch; ch = getchar(); if(# = ch & i MaxStLength) sti = ch; Identify(st); else printf(输入出错！n); getchar();v

9、oid Init() int i,j; vnNum = 0; vtNum = 0; PNum = 0; for(i = 0; i = MaxVnNum; i+) Vni = 0; for(i = 0; i = MaxVtNum; i+) Vti = 0; for(i = 0; i MaxRuleNum; i+) Pi.lCursor = NULL; Pi.rHead = NULL; Pi.rLength = 0; PNum = 0; for(i = 0; i = MaxPLength; i+) bufferi = 0; for(i = 0; i MaxVnNum; i+) firsti = N

10、ULL; followi = NULL; for(i = 0; i = MaxVnNum; i+) for(j = 0; j = MaxVnNum + 1; j+) analyseTableij = -1; /*返回Vn在Vn表中的位置+100、Vt在Vt表中的位置，-1表示未找到*/int IndexCh(char ch) int n; n = 0; /*is Vn?*/ while(ch != Vnn & 0 != Vnn) n+; if(0 != Vnn) return 100 + n; n = 0; /*is Vt?*/ while(ch != Vtn & 0 != Vtn) n+;

11、if(0 != Vtn) return n; return -1;/*输出Vn或Vt的内容*/void ShowChArray(char* collect) int k = 0; while(0 != collectk) printf( %c , collectk+); printf(n);/*输入非终结符*/void InputVn() int inErr = 1; int n,k; char ch; while(inErr) printf(n请输入所有的非终结符，注意：); printf(请将开始符放在第一位，并以#号结束:n); ch = ; n = 0; /*初始化数组*/ while

12、(n MaxVnNum) Vnn+ = 0; n = 0; while(# != ch) & (n MaxVnNum) if( != ch & n != ch & -1 = IndexCh(ch) Vnn+ = ch; vnNum+; ch = getchar(); Vnn = #; /*以#标志结束用于判断长度是否合法*/ k = n; /*k用于记录n以便改Vnn=0*/ if(# != ch) if( # != (ch = getchar() while(# != (ch = getchar() ; printf(n符号数目超过限制！n); inErr = 1; continue; /*

13、正确性确认，正确则，执行下下面，否则重新输入*/ Vnk = 0; ShowChArray(Vn); ch = ; while(y != ch & n != ch) if(n != ch) printf(输入正确确认?(y/n):); scanf(%c, &ch); if(n = ch) printf(录入错误重新输入！n); inErr = 1; else inErr = 0; /*输入终结符*/void InputVt() int inErr = 1; int n,k; char ch; while(inErr) printf(n请输入所有的终结符，注意：); printf(以#号结束:n

14、); ch = ; n = 0; /*初始化数组*/ while(n MaxVtNum) Vtn+ = 0; n = 0; while(# != ch) & (n MaxVtNum) if( != ch & n != ch & -1 = IndexCh(ch) Vtn+ = ch; vtNum+; ch = getchar(); Vtn = #; /*以#标志结束*/ k = n; /*k用于记录n以便改Vtn=0*/ if(# != ch) if( # != (ch = getchar() while(# != (ch = getchar() printf(n符号数目超过限制！n); inE

15、rr = 1; continue; /*正确性确认，正确则，执行下下面，否则重新输入*/ Vtk = 0; ShowChArray(Vt); ch = ; while(y != ch & n != ch) if(n != ch) printf(输入正确确认?(y/n):); scanf(%c, &ch); if(n = ch) printf(录入错误重新输入！n); inErr = 1; else inErr = 0; /*产生式输入*/void InputP() char ch; int i = 0, n,num; printf(请输入文法产生式的个数：); scanf(%d, &num);

16、 PNum = num; getchar(); /*消除回车符*/ printf(n请输入文法的%d个产生式,并以回车分隔每个产生式：, num); printf(n); while(i num) printf(第%d个：, i); /*初始化*/ for(n =0; n MaxPLength; n+) buffern = 0; /*输入产生式串*/ ch = ; n = 0; while(n != (ch = getchar() & n rCursor = IndexCh(buffer3); pt-next = NULL; Pi.rHead = pt; n = 4; while(0 != b

17、uffern) qt = (pRNode*)malloc(sizeof(pRNode); qt-rCursor = IndexCh(buffern); qt-next = NULL; pt-next = qt; pt = qt; n+; Pi.rLength = n - 3; i+; /*调试时使用*/ else printf(输入符号含非法在成分，请重新输入！n); /*判断产生式正确性*/bool CheckP(char * st) int n; if(100 IndexCh(st0) return false; if(- != st1) return false; if( != st2)

18、 return false; for(n = 3; 0 != stn; n +) if(-1 = IndexCh(stn) return false; return true;/*=first & follow=*/*计算first集,U-xx.*/void First(int U) int i,j; for(i = 0; i PNum; i+) if(Pi.lCursor = U) struct pRNode* pt; pt = Pi.rHead; j = 0; while(j pt-rCursor) /*注:此处因编程出错,使空产生式时 rlength同样是1,故此处同样可处理空产生式*/

19、 AddFirst(U, pt-rCursor); break; else if(NULL = firstpt-rCursor - 100) First(pt-rCursor); AddFirst(U, pt-rCursor); if(!HaveEmpty(pt-rCursor) break; else pt = pt-next; j+; if(j = Pi.rLength) /*当产生式右部都能推出空时*/ AddFirst(U, -1); /*加入first集*/void AddFirst(int U, int nCh) /*当数值小于100时nCh为Vt*/*当处理非终结符时,AddFi

20、rst不添加空项(-1)*/ struct collectNode *pt, *qt; int ch; /*用于处理Vn*/ pt = NULL; qt = NULL; if(nCh nVt = nCh) break; else qt = pt; pt = pt-next; if(NULL = pt) pt = (struct collectNode *)malloc(sizeof(struct collectNode); pt-nVt = nCh; pt-next = NULL; if(NULL = firstU - 100) firstU - 100 = pt; else qt-next

21、= pt; /*qt指向first集的最后一个元素*/ pt = pt-next; else pt = firstnCh - 100; while(NULL != pt) ch = pt-nVt; if(-1 != ch) AddFirst(U, ch); pt = pt-next; /*判断first集中是否有空(-1)*/bool HaveEmpty(int nVn) if(nVn nVt) return true; pt = pt-next; return false;/*计算follow集,例：U-xVy,U-xV.(注：初始符必含#-1)*/void Follow(int V) in

22、t i; struct pRNode *pt ; if(100 = V) /*当为初始符时*/ AddFollow(V, -1, 0 ); for(i = 0; i rCursor != V) /*注此不能处理：U-xVyVz的情况*/ pt = pt-next; if(NULL != pt) pt = pt-next; /*V右侧的符号*/ if(NULL = pt) /*当V后为空时V-xV，将左符的follow集并入V的follow集中*/ if(NULL = followPi.lCursor - 100 & Pi.lCursor != V) Follow(Pi.lCursor); Ad

23、dFollow(V, Pi.lCursor, 0); else /*不为空时V-xVy,(注意：y-)，调用AddFollow加入Vt或y的first集*/ while(NULL != pt & HaveEmpty(pt-rCursor) AddFollow(V, pt-rCursor, 1); /*y的前缀中有空时，加如first集*/ pt = pt-next; if(NULL = pt) /*当后面的字符可以推出空时*/ if(NULL = followPi.lCursor - 100 & Pi.lCursor != V) Follow(Pi.lCursor); AddFollow(V,

24、 Pi.lCursor, 0); else /*发现不为空的字符时*/ AddFollow(V, pt-rCursor, 1); /*当数值小于100时nCh为Vt*/*#用-1表示,kind用于区分是并入符号的first集，还是follow集kind = 0表加入follow集，kind = 1加入first集*/void AddFollow(int V, int nCh, int kind) struct collectNode *pt, *qt; int ch; /*用于处理Vn*/ pt = NULL; qt = NULL; if(nCh nVt = nCh) break; else

25、qt = pt; pt = pt-next; if(NULL = pt) pt = (struct collectNode *)malloc(sizeof(struct collectNode); pt-nVt = nCh; pt-next = NULL; if(NULL = followV - 100) followV - 100 = pt; else qt-next = pt; /*qt指向follow集的最后一个元素*/ pt = pt-next; else /*为非终结符时，要区分是加first还是follow*/ if(0 = kind) pt = follownCh - 100;

26、while(NULL != pt) ch = pt-nVt; AddFollow(V, ch, 0); pt = pt-next; else pt = firstnCh - 100; while(NULL != pt) ch = pt-nVt; if(-1 != ch) AddFollow(V, ch, 1); pt = pt-next; /*输出first或follow集*/void ShowCollect(struct collectNode *collect) int i; struct collectNode *pt; i = 0; while(NULL != collecti) pt

27、 = collecti; printf(n%c:t, Vni); while(NULL != pt) if(-1 != pt-nVt) printf( %c, Vtpt-nVt); else printf( #); pt = pt-next; i+; printf(n);/*计算first和follow*/void FirstFollow() int i; i = 0; while(0 != Vni) if(NULL = firsti) First(100 + i); i+; i = 0; while(0 != Vni) if(NULL = followi) Follow(100 + i);

28、i+; /*=构造预测分析表,例：U:xyz=*/void CreateAT() int i; struct pRNode *pt; struct collectNode *ct; for(i = 0; i rCursor) /*处理非终结符，当为终结符时，定含空为假跳出*/ ct = firstpt-rCursor - 100; while(NULL != ct) if(-1 != ct-nVt) analyseTablePi.lCursor - 100ct-nVt = i; ct = ct-next; pt = pt-next; if(NULL = pt) /*NULL = pt，说明xy

29、z-,用到follow中的符号*/ ct = followPi.lCursor - 100; while(NULL != ct) if(-1 != ct-nVt) analyseTablePi.lCursor - 100ct-nVt = i; else /*当含有#号时*/ analyseTablePi.lCursor - 100vtNum = i; ct = ct-next; else if(100 rCursor) /*不含空的非终结符*/ ct = firstpt-rCursor - 100; while(NULL != ct) analyseTablePi.lCursor - 100c

30、t-nVt = i; ct = ct-next; else /*终结符或者空*/ if(-1 = pt-rCursor) /*-1为空产生式时*/ ct = followPi.lCursor - 100; while(NULL != ct) if(-1 != ct-nVt) analyseTablePi.lCursor - 100ct-nVt = i; else /*当含有#号时*/ analyseTablePi.lCursor - 100vtNum = i; ct = ct-next; else /*为终结符*/ analyseTablePi.lCursor - 100pt-rCursor

31、= i; /*输出分析表*/void ShowAT() int i,j; printf(构造预测分析表如下：n); printf(t|t); for(i = 0; i vtNum; i+) printf(%ct, Vti); printf(#tn); printf(- - -t|- - -t); for(i = 0; i = vtNum; i+) printf(- - -t); printf(n); for(i = 0; i vnNum; i+) printf(%ct|t, Vni); for(j = 0; j analyseStacktopAnalyse) /*当为终结符时*/ if(ana

32、lyseStacktopAnalyse = IndexCh(stcurrent) /*匹配出栈，指示器后移*/ Pop(); current+; step+; printf(%dt, step); ShowStack(); printf(tt%ctt出栈、后移n, stcurrent); else printf(%c-%c不匹配！, analyseStacktopAnalyse, stcurrent); printf(此串不是此文法的句子！n); return; else /*当为非终结符时*/ r = analyseTableanalyseStacktopAnalyse - 100IndexCh(stcurrent); if(-1 != r) Push(r