consecutive lines in a file

[Luba Pardo]

Dear sir/madam:
I am trying to write a script to process to consecutive lines at a time and
compare elements of between two consecutive lines.
I tried something like:
$i=0;
while (<IN>){
chomp;
@a1_s= split/\</, $_{$I];
@a2_s= split/\</,$_[$i+1];

if ($a1_s[1] =~ /HG-Stats_gi1/){

@temp  = split/>/, $a1_s[1];
@temp1 = split/>/, $a2_s[1];

         print " line is $i, array is @a1_s, array 2 es @a2_s\n";
}
$i++;

}

close IN;

but it does not work. I guess the $_[$i] and $_[$i+1] does not work, but I
do not exactly how.

Could anyone give any idea why?

Thanks in advance



Luba Pardo