#include<stdio.h>
#include<string.h>
#include<stdlib.h>
void removeduplicate();
void final();
int Isiden(char ch);
int Isop(char ch);
int Isdel(char ch);
int Iskey(char * str);
void removeduplicate();
char op[8]={'+','-','*','/','=','<','>','%'};
char del[8]={'}','{',';','(',')','[',']',','};
char *key[]={"int","void","main","char","float"};
//char *operato[]={"+","-","/","*","<",">","=","%","<=",">=","++"};
int idi=0,idj=0,k,opi=0,opj=0,deli=0,uqdi=0,uqidi=0,uqoperi=0,kdi=0,liti=0,ci=0;
int uqdeli[20],uqopi[20],uqideni[20],l=0,j;
char uqdel[20],uqiden[20][20],uqop[20][20],keyword[20][20];
char iden[20][20],oper[20][20],delem[20],litral[20][20],lit[20],constant[20][20];
void lexanalysis(char *str)
{
int i=0;
while(str[i]!='\0')
{
if(Isiden(str[i])) //for identifiers
{
while(Isiden(str[i]))
{
iden[idi][idj++]=str[i++];
}
iden[idi][idj]='\0';
idi++;idj=0;
}
else
if(str[i]=='"') //for literals
{
lit[l++]=str[i];
for(j=i+1;str[j]!='"';j++)
{
lit[l++]=str[j];
}
lit[l++]=str[j];lit[l]='\0';
strcpy(litral[liti++],lit);
i=j+1;
}
else
if(Isop(str[i])) // for operators
{
while(Isop(str[i]))
{
oper[opi][opj++]=str[i++];
}
oper[opi][opj]='\0';
opi++;opj=0;
}
else
if(Isdel(str[i])) //for delemeters
{
while(Isdel(str[i]))
{
delem[deli++]=str[i++];
}
}
else
{
i++;
}
}
removeduplicate();
final();
}
int Isiden(char ch)
{
if(isalpha(ch)||ch=='_'||isdigit(ch)||ch=='.')
return 1;
else
return 0;
}
int Isop(char ch)
{
int f=0,i;
for(i=0;i<8&&!f;i++)
{
if(ch==op[i])
f=1;
}
return f;
}
int Isdel(char ch)
{
int f=0,i;
for(i=0;i<8&&!f;i++)
{
if(ch==del[i])
f=1;
}
return f;
}
int Iskey(char * str)
{
int i,f=0;
for(i=0;i<5;i++)
{
if(!strcmp(key[i],str))
f=1;
}
return f;
}
void removeduplicate()
{
int i,j;
for(i=0;i<20;i++)
{
uqdeli[i]=0;
uqopi[i]=0;
uqideni[i]=0;
}
for(i=1;i<deli+1;i++) //removing duplicate delemeters
{
if(uqdeli[i-1]==0)
{
uqdel[uqdi++]=delem[i-1];
for(j=i;j<deli;j++)
{
if(delem[i-1]==delem[j])
uqdeli[j]=1;
}
}
}
for(i=1;i<idi+1;i++) //removing duplicate identifiers
{
if(uqideni[i-1]==0)
{
strcpy(uqiden[uqidi++],iden[i-1]);
for(j=i;j<idi;j++)
{
if(!strcmp(iden[i-1],iden[j]))
uqideni[j]=1;
}
}
}
for(i=1;i<opi+1;i++) //removing duplicate operators
{
if(uqopi[i-1]==0)
{
strcpy(uqop[uqoperi++],oper[i-1]);
for(j=i;j<opi;j++)
{
if(!strcmp(oper[i-1],oper[j]))
uqopi[j]=1;
}
}
}
}
void final()
{
int i=0;
idi=0;
for(i=0;i<uqidi;i++)
{
if(Iskey(uqiden[i])) //identifying keywords
strcpy(keyword[kdi++],uqiden[i]);
else
if(isdigit(uqiden[i][0])) //identifying constants
strcpy(constant[ci++],uqiden[i]);
else
strcpy(iden[idi++],uqiden[i]);
}
// printing the outputs
printf("\n\tDelemeter are : \n");
for(i=0;i<uqdi;i++)
printf("\t%c\n",uqdel[i]);
printf("\n\tOperators are : \n");
for(i=0;i<uqoperi;i++)
{
printf("\t");
puts(uqop[i]);
}
printf("\n\tIdentifiers are : \n");
for(i=0;i<idi;i++)
{
printf("\t");
puts(iden[i]);
}
printf("\n\tKeywords are : \n");
for(i=0;i<kdi;i++)
{
printf("\t");
puts(keyword[i]);
}
printf("\n\tConstants are :\n");
for(i=0;i<ci;i++)
{
printf("\t");
puts(constant[i]);
}
printf("\n\tLiterals are :\n");
for(i=0;i<liti;i++)
{
printf("\t");
puts(litral[i]);
}
}
void main()
{
char str[50];
//clrscr();
printf("\nEnter the string : ");
scanf("%[^\n]c",str);
lexanalysis(str);
//getch();
}
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