#include<stdio.h>
#include <ctype.h>
#define ok 1
#define error 0
#define MAXREGLUARLONG 40
#define MAXSTATELONG 40
#define MAXCAHRSLONG 40
typedef int state;
int iCurrentState=0; //初态以1开始
int iPreState=0;
int iLastForkState=0;
int iForkState=0;
int iMaxState=0;
char cRegluarSting[MAXREGLUARLONG]; //输入的正规式字符串
char cCharSet[MAXCAHRSLONG]; //字符集
int iStateMatrix[MAXSTATELONG][MAXCAHRSLONG]; //状态转换矩阵
state vStoreRegluarSting()//把字符串读入一个缓冲区中
{
scanf("%s",cRegluarSting);
return ok;
}
state vPreProcessRegluarSting()
//对字符串进行预处理,去掉字符串里面的对分析不产生影响
{
int i=0;
while(cRegluarSting[i]!=' ')
{
if(cRegluarSting[i]=='*')
{
int j=i+1;
while(cRegluarSting[j-1]!=' ')
{
cRegluarSting[j-1]=cRegluarSting[j++];
}
}
i++;
}
return ok;
}
void vConstructStateMatrix(char cChar,int istate)//构造状态转换矩阵
{
int i;
for(i=0;cCharSet[i]!=' ';i++)
if(cChar==cCharSet[i])
break;
cCharSet[i]=cChar;
iStateMatrix[iPreState][i]=istate;
}
void vAanalyseRegluarSting()//对字符串进行从左到右的分析与处理
{
int i=0;
for(i=0;cRegluarSting[i]!=0;i++)
{
if(cRegluarSting[i]=='(') //NFA出现开始分叉情况
{
int iTheFirstl=0;
int iCharNumBeforl=0;
iForkState=iCurrentState;
while(cRegluarSting[i]!=')')
{
i++;
if(isalpha(cRegluarSting[i]))
{
if(cRegluarSting[i+1]==')')
iCurrentState=iLastForkState;
else
iCurrentState++;
iCharNumBeforl++; vConstructStateMatrix(cRegluarSting[i],iCurrentState);
iPreState=iCurrentState;
if(iCurrentState>iMaxState)
iMaxState=iCurrentState;
}
if(cRegluarSting[i]=='|')
{
iPreState=iForkState;
if(iTheFirstl==0)
{
iLastForkState=iCurrentState;
iTheFirstl++;
}
if(iCharNumBeforl==1&&cRegluarSting[i+2]=='|')
iCurrentState=iForkState;
iCharNumBeforl=0;
}
if(cRegluarSting[i]==')')
{
iPreState=iForkState=iLastForkState;
iCurrentState=iMaxState;
}
}
}
else
{
if(isalpha(cRegluarSting[i]))
{
iCurrentState++; vConstructStateMatrix(cRegluarSting[i],iCurrentState);
iPreState=iCurrentState;
if(iCurrentState>iMaxState)
iMaxState=iCurrentState;
}
}
}
}
void vPrintfStateProjectFunction()
{
int icCharSetPointer;
int iPreStatePointer;
for
(iPreStatePointer=0;iPreStatePointer<MAXSTATELONG;iPreStatePointer++)
for(icCharSetPointer=0;icCharSetPointer<MAXSTATELONG;icCharSetPointer++)
if(iStateMatrix[iPreStatePointer][icCharSetPointer]>0) printf("&(%d,%c)=%d
",iPreStatePointer,cCharSet[icCharSetPointer],iStateMatrix[iPreStatePointer][icCharSetPointer]);
}
void vPrintfNfa()//输出NFA
{
int iStateNumble;
int i=0;
printf("NFA的形式为:(S,$,&,S0,F)
以下为NFA的具体集合内容:
");
printf("字符集$为:{");
while(cCharSet[i]!=0)
if(cCharSet[i+1]==0)
printf("%c",cCharSet[i++]);
else
printf("%c,",cCharSet[i++]);
printf("}
");
printf("
状态集S为:{");
for (i=0;i<=iMaxState;i++) {
if(i==iMaxState)
printf("%d",i);
else
printf("%d,",i);
}
printf("}
");
vPrintfStateProjectFunction();
printf("
初态集S0为:{0}
");
printf("终态集F为:{%d}",iMaxState);
}
void main()
{
vStoreRegluarSting();
vPreProcessRegluarSting();
vAanalyseRegluarSting();
vPrintfNfa();
}