编译原理-LL(1)文法源代码（实验三）

if(100 > pt->rCursor) {

AddFirst(U, pt->rCursor); break; } else {

if(NULL == first[pt->rCursor - 100]) {

First(pt->rCursor); }

AddFirst(U, pt->rCursor); if(!HaveEmpty(pt->rCursor)) {

break; } else {

pt = pt->next; } } j++; }

if(j >= P[i].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) {

struct collectNode *pt, *qt; int ch; /*用于处理Vn*/ pt = NULL; qt = NULL; if(nCh < 100) {

pt = first[U - 100]; while(NULL != pt) {

if(pt->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 == first[U - 100]) {

first[U - 100] = pt; } else {

qt->next = pt; /*qt指向first集的最后一个元素*/ }

pt = pt->next; } } else {

pt = first[nCh - 100]; while(NULL != pt) {

ch = pt->nVt; if(-1 != ch) {

AddFirst(U, ch); }

pt = pt->next; } } }

bool HaveEmpty(int nVn) {

if(nVn < 100) return false;

struct collectNode *pt; pt = first[nVn - 100]; while(NULL != pt)

{

if(-1 == pt->nVt) return true; pt = pt->next; }

return false; }

void Follow(int V) { int i;

struct pRNode *pt ;

if(100 == V) /*当为初始符时*/ AddFollow(V, -1, 0 ); for(i = 0; i < PNum; i++) {

pt = P[i].rHead;

while(NULL != pt && pt->rCursor != V) pt = pt->next; if(NULL != pt) {

pt = pt->next; if(NULL == pt) {

if(NULL == follow[P[i].lCursor - 100] && P[i].lCursor != V) {

Follow(P[i].lCursor); }

AddFollow(V, P[i].lCursor, 0); } else {

while(NULL != pt && HaveEmpty(pt->rCursor)) {

AddFollow(V, pt->rCursor, 1); pt = pt->next; }

if(NULL == pt) {

if(NULL == follow[P[i].lCursor - 100] && P[i].lCursor != V) {

Follow(P[i].lCursor); }

AddFollow(V, P[i].lCursor, 0); } else {

AddFollow(V, pt->rCursor, 1); } } } } }

void AddFollow(int V, int nCh, int kind) {

struct collectNode *pt, *qt; int ch; pt = NULL; qt = NULL;

if(nCh < 100) /*为终结符时*/ {

pt = follow[V - 100]; while(NULL != pt) {

if(pt->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 == follow[V - 100]) {

follow[V - 100] = pt; } else {

qt->next = pt; /*qt指向follow集的最后一个元素*/ }