求 编译原理 语法分析程序

#include <iostream>

#include <cstdio>

#include <cstdlib>

#include <cstring>

#include <stack>

using namespace std

struct Node1

{

char vn

char vt

char s[10]

}MAP[20]//存储分析预测表每个位置对应的终结符，非终结符，产生式

int k

//用R代表E',W代表T',e代表空

char G[10][10]={"E->TR","R->+TR","R->e","T->FW","W->*FW","W->e","F->(E)","F->i"}//存储文法中的产吵唯生式

char VN[6]={'E','R','T','W','F'}//存储非终结符

char VT[6]={'i','+','*','(',')','#'}//存储终结符

char SELECT[10][10]={"(,i","+","),#","雹碰败(,i","*","+,),#","(","i"}//存储文法中每个产生式对应的SELECT集

char Right[10][8]={"->TR","->+TR","->e","->FW","->*FW","->e","->(E)","->i"}

stack <char>stak,stak1,stak2

bool compare(char *a,char *b)

{

int i,la=strlen(a),j,lb=strlen(b)

for(i=0i<lai++)

for(j=0j<lbj++)

{

if(a[i]==b[j])

return 1

}

return 0

}

char *Find(char vn,char vt)

{

int i

for(i=0i<ki++)

{

if(MAP[i].vn==vn &&MAP[i].vt==vt)

return MAP[i].s

}

return "error"

}

char * Analyse(char * word)

{

char p,action[10],output[10]

int i=1,j,l=strlen(word),k=0,l_act,m

while(!stak.empty())

stak.pop()

stak.push('#')

stak.push('E')

printf("________________________________________________________________________________\n")

printf("\n对符号串%s的分析过程\n",word)

printf("步骤栈顶元素剩余输入串推到所用产生式或匹配\n")

p=stak.top()

while(p!='#')

{

printf("%7d "源颤,i++)

p=stak.top()

stak.pop()

printf("%6c ",p)

for(j=k,m=0j<lj++)

output[m++]=word[j]

output[m]='\0'

printf("%10s",output)

if(p==word[k])

{

if(p=='#')

{

printf("接受\n")

return "SUCCESS"

}

printf(" “%c”匹配\n",p)

k++

}

else

{

strcpy(action,Find(p,word[k]))

if(strcmp(action,"error")==0)

{

printf("没有可用的产生式\n")

return "ERROR"

}

printf("%c%s\n",p,action)

int l_act=strlen(action)

if(action[l_act-1]=='e')

continue

for(j=l_act-1j>1j--)

stak.push(action[j])

}

}

if(strcmp(output,"#")!=0)

return "ERROR"

}

int main ()

{

freopen("in.txt","r",stdin)

//freopen("out.txt","w",stdout)

char source[100]

int i,j,flag,l,m

printf("\n*****为了方便编写程序，用R代表E',W代表T',e代表空*****\n\n")

printf("该文法的产生式如下：\n")

for(i=0i<8i++)

printf(" %s\n",G[i])

printf("________________________________________________________________________________\n")

printf("\n该文法的SELECT集如下：\n")

for(i=0i<8i++)

{

printf(" SELECT(%s) = { %s }\n",G[i],SELECT[i])

}

printf("________________________________________________________________________________\n")

//判断是否是LL(1)文法

flag=1

for(i=0i<8i++)

{

for(j=i+1j<8j++)

{

if(G[i][0]==G[j][0])

{

if(compare(SELECT[i],SELECT[j]))

{

flag=0break

}

}

}

if(j!=8)

break

}

if(flag)

printf("\n有相同左部产生式的SELECT集合的交集为空，所以文法是LL（1）文法。\n")

else

printf("\n有相同左部产生式的SELECT集合的交集不为空，所以文法不是LL（1）文法。\n")

printf("________________________________________________________________________________\n")

//预测分析表

for(i=0,k=0i<8i++)

{

l=strlen(SELECT[i])

for(j=0j<lj+=2)

{

MAP[k].vn=G[i][0]

MAP[k].vt=SELECT[i][j]

strcpy(MAP[k].s,Right[i])

k++

}

}

printf("\n表达式文法的预测分析表如下：\n\n")

printf(" ")

for(i=0i<6i++)

printf("%10c",VT[i])

printf("\n")

for(i=0i<5i++)

{

printf("---------------------------------------------------------------\n")

printf("%10c",VN[i])

for(j=0j<6j++)

{

for(m=0m<km++)

{

if(VN[i]==MAP[m].vn &&VT[j]==MAP[m].vt)

{

printf("%10s",MAP[m].s)

break

}

}

if(m==k)

printf(" ")

}

printf("\n")

}

/*预测分析程序

Analyse函数*/

//输入源文件串

while(cin>>source)

{

printf("\n分析结果：%s\n\n",Analyse(source))

}

while(1)

return 0

}

#include <iostream>

using namespace std

#define m 45

#define n 100

#define t 10

int main()

{

FILE *fp

char filename[20],c[n]

printf("Type the file name which you want to open:")

scanf("%s",&filename)

fp=fopen(filename,"r+")/*以r-只读方式打开指定文件*/

if((fp=fopen(filename,"r"))==NULL) /*文件不存在输出错误*/

{cout<<"文件不存在!"<<endlexit(-1)}

cout<<"文件中内容如下:"<<endl

for(int j=0!feof(fp)j++){

c[j]=fgetc(fp)//从流中读取字符

}

char keyword[m][t]={"include","int","string","cout","cin","auto","break","case","char","class","const",

"continue","default","delete","do","double","else","enum","extern","float","for","friend","if","inline",

"int","long","new","operator","private","protected","public","register","return","short","sizeof","static",

"struct","switch","template","this","typedef","union","virtual","void","while"}//关键字数组

char a[t],*p=c,*q=a,*s=a

bool w=0,r=0

int i=0

for(i=0i<10i++)a[i]=NULL//初始化临时数组

while (*p !=NULL){

q=s=a

if((*p>='a'&&*p<='z')||(*p>='A'&&*p<='Z')||*p=='_'){//识别标识符

*q=*pp++q++

while ((*p>='a'&&*p<='z')||(*p>='A'&&*p<='Z')||(*p>='0'&&*p<='9')||*p=='_'){

*q=*pp++q++

}

for(i=0i<mi++)if(strcmp(keyword[i],a)==0){r=1break}

if(r==1){cout<<"关键字为:"r=0}

else cout<<"标识符为:"

while(s!=q){

cout<<*s

s++

}

cout<<endl

for(i=0i<ti++)a[i]=NULL

}

else if(*p=='\''){//识辩盯缺别字符常量

p++

while(*p!='\''){

*q=*p

p++

q++

}

cout<<"字符常量为:"

while(s!=q){

cout<<*s

s++

}

cout<<endl

for(i=0i<ti++)a[i]=NULL

p++

}

else if(*p=='\"'){//识别字符串常量

p++

while(*p!='\"'){

*q=*p

p++

q++

}

cout<<"字符串常量为:"

while(s!=q){

cout<携辩<*s

s++

}

cout<<endl

for(i=0i<ti++)a[i]=NULL

p++

}

else if(*p=='+'||*p=='-'||*p=='*'||*p=='/'||*p=='='||*p=='%'||*p=='/'){//识别运算符

cout<<"运算符为:"<<*p

cout<<endl

p++

}

else if(*p==''||*p==','){//识别分解符

cout<<"分界符为:"<<*p

cout<<则升endl

p++

}

else if(*p>='0'&&*p<='9'){

s=q=a

*q=*pp++q++

while(*p>='0'&&*p<='9'||*p=='.'){

*q=*pp++q++

}

while(s!=q){

if(*s=='.'){w=1break}//识别实型常量

s++

}

s=a

if(w ==1){

cout<<"实型常量为:"

while(s!=q){

cout<<*s

s++

}

for(i=0i<ti++)a[i]=NULL

}

else {

cout<<"整型常量为:"

while(s!=q){//识别整型常量

cout<<*s

s++

}

for(i=0i<ti++)a[i]=NULL

}

cout<<endl

}

else p++

}

return 0

}

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