hi, you can do this using just a single array.

my @a=(15,24,23,110,30,58,3,22,79,6);
my $wantedSentence = 250;
my $chptr = 1;
foreach (@a) {
   $wantedSentence -= $_;
   if ($wantedSentence <= 0) {
       print "$chptr";
       last;
   }
   $chptr++;
}
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