fir.c

#include<stdio.h>
#include<ctype.h>
void FIRST(char);
int count,n=0;
char prodn[10][10],first[10];
int main()
{
	int i,choice;
	char c,ch;
	printf("No of productions:");
	scanf("%d",&count);
	printf("\nEnter %d productions epsilon =$:\n\n",count);
	for(i=0;i<count;i++)
	{
		scanf("%s%c",prodn[i],&ch);
//		printf("char=%c",ch);
	}
	do{
		n=0;
		printf("\nEnter element to find First Funciton of:");
		scanf("%c",&c);
		FIRST(c);
		printf("\n FIRST(%c)={",c);
		for(i=0;i<n;i++)
		printf("%c",first[i]);
		printf("}\n");
		printf("press 1 to continue");
		scanf("%d%c",&choice,&ch);
	}
	while(choice==1);
}


void FIRST(char c)
{
	int j;
	if(!(isupper(c)))first[n++]=c;
	for(j=0;j<count;j++)
	{
		if(prodn[j][0]==c)
		{
			if(prodn[j][2]=='$') first[n++]='$';
			else if(islower(prodn[j][2])) first[n++]=prodn[j][2];
			else FIRST(prodn[j][2]);
		}
	}
}