#!/usr/bin/perl
# w5.10.pl find a string - fast 
# Usage:  time w5.10.pl king ~horn/public/tc441/e2/act1

open (FH, "$ARGV[1]") or die("Can't open $ARGV[1]");
while (<FH>) {
   if (m/$ARGV[0]/i){                               
      print ("$_");                                      
   }                                              
}
close (FH);