Identifying words of length 4-8 characters long.

%{
#include<stdio.h.>
int a=0;
%}

%%
[a-zA-Z0-9._]+ {a=yyleng; if(a==4||a==5||a==6||a==7||a==8) printf("Word accepted");}
%%

main()
{
yylex();
}

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