Yes, kevbot's solution with a hash is good. Here is what I typed while keybot was also typing - this preserves the numbers in each row if more calculations are needed. If there are only 30 rows, a hash of array is a good idea. If there are 100,000 rows, that advice would change. Here the hash gets rid of the need to deal with index[0] of the array of array (2-D array). A more efficient way can be done by processing row by row and outputting a line result when the first number changes. 
#!usr/bin/perl
use strict;
use warnings;
use Data::Dumper;

my %HoA;  # a Hash of Array

while (my $line = <DATA>)
{ 
   my ($bucket, $num) = $line =~ m/^\s*(\d+)\s*\|\s*(\d+)/;
   push @{$HoA{$bucket}},$num;
}


my $total;

foreach my $key (sort {$a<=>$b} keys %HoA)
{
   my $line_total;
   
   foreach my $num (@{$HoA{$key}})
   {
      $line_total += $num;
   }
   
   print "Line $key total = $line_total\n";
   $total += $line_total;
}
print "Grand Total = $total\n";

=Prints
Line 1 total = 150
Line 2 total = 75
Line 3 total = 55
Grand Total = 280
=cut

__DATA__
1|10
1|20
1|30
1|40
1|50
2|15
2|25
2|35
3|1
3|2
3|3
3|4
3|5
3|6
3|7
3|8
3|9
3|10

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In reply to Re: array of arrays by Marshall
in thread array of arrays by virtualweb

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