%{
/* Definition section */
#include<stdio.h>
#include <stdlib.h>
void yyerror(const char *str)
{
printf("\nSequence Rejected\n");		
}
 
%}
 
%token ZERO ONE
 
/* Rule Section */
%%
 
r : s {printf("\nSequence Accepted\n\n");}
;
 
s : n
| ZERO a
| ONE b
;
 
a : n a
| ZERO
;
 
b : n b
| ONE
;
 
n : ZERO
| ONE
;
 
%%
 
#include"lex.yy.c"
//driver code
int main()
{
	printf("\nEnter Sequence of Zeros and Ones : ");
	yyparse();
	printf("\n");
	return 0;
}
 

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