Lex program to find the length of the longest word

 /*Write a Lex program that finds the length of the longest word (defined as a contiguous

 string of upper and lower case letters) in the input.*/

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

%%
[a-zA-Z]+ {
if(yyleng>k)
{  k= yyleng;
}
}
%%

int main(int argc[],char **argv[])
{
 yyin=fopen("abc.txt","r");
 yylex(); 
 printf("largest: %d",k);
 printf("\n");
 return 0;
}

 //file abc.txt

Lex program to find the length of the longest word

//Output of the above program

Lex program to find the length of the longest word

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