How do you write c program to identify keywords using transition table?

Answer 1

#include

#include

#include

void keyw(char str[10])

{

if(strcmp("for",str)==0)

printf("%s is a keyword",str);

else if(strcmp("while",str)==0)

printf("%s is a keyword",str);

else if(strcmp("char",str)==0)

printf("%s is a keyword",str);

else if(strcmp("int",str)==0)

printf("%s is a keyword",str);

else if(strcmp("if",str)==0)

printf("%s is a keyword",str);

else if(strcmp("else",str)==0)

printf("%s is a keyword",str);

else

printf("%s is an identifier",str);

printf("\n");

}

main()

{

FILE *f1,*f2,*f3;

char c,str[10];

int num[100],ln=0,tvalue=0,i=0,j=0,k=0;

printf("Enter a C program expression");

f1=fopen("input.c","w");

while((c=getchar())!=EOF)

fputc(c,f1);

f1=fopen("input.c","r");

f2=fopen("identifier.txt","w");

f3=fopen("specialchars.txt","w");

while((c=fgetc(f1))!=EOF)

{

if(isdigit(c))

{

tvalue=c-'0';

c=fgetc(f1);

while(isdigit(c))

{

tvalue=tvalue*10+c-'0';

c=fgetc(f1);

}

num[i++]=tvalue;

ungetc(c,f1);

}

else if(isalpha(c))

{

fputc(c,f2);

c=fgetc(f1);

while((isdigit(c))isalpha(c)c==' 'c=='$')

{

fputc(c,f2);

c=fgetc(f1);

}

fputc(' ',f2);

ungetc(c,f1);

}

else if(c==' 'c=='\t');

else if(c=='\n')

ln++;

else

fputc(c,f3);

}

fclose(f1);

fclose(f2);

fclose(f3);

printf("Numbers in the program are \n");

for(j=0;j

printf("%d",num[j]);

printf("\n");

f2=fopen("identifier.txt","r");

k=0;

while((c=fgetc(f2))!=EOF)

{

if(c!=' ')

str[k++]=c;

else

{

str[k]='\0';

keyw(str);

k=0;

}

}

fclose(f2);

f3=fopen("specialchars.txt","r");

printf("The special chars in the pgm are \n");

while((c=fgetc(f3))!=EOF)

printf("%c",c);

printf("\n");

fclose(f3);

}