Write a program to recognize the grammar anbman 0<=n<=m

Lex file:

%{
#include "y.tab.h"
%}

%%
[a] return a;
[b] return b;
[bb] return bb;
%%
  

Yacc file:

%{
#include<stdio.h>
%}

%token a b bb

%%
S : E {printf("String accepted");}
   :
E : E T
    | T
    ;
T : a
    | b
    | bb
    ;
%%

main()
{
yyparse();
}
yyerror(char **arg)
{
printf("Invalid string");
}

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