Just put your data into a hash of arrays, and then loop on the compiled data using List::Util->max to determine the max value in each array.

The below snippet demonstrates what I'm talking about with the fake data you listed:

use List::Util qw(max);

use strict;
use warnings;

my %vals;

# Put Data into a Hash of Arrays
while (<DATA>) {
    chomp;
    my ($key, $val) = split;
    push @{$vals{$key}}, $val;
}

for my $key (sort {$a <=> $b} keys %vals) {
    my $max = max @{$vals{$key}};
    print "$key $max\n";
}

=prints
1 4
2 7
3 10
=cut

__DATA__
1  3
1  2
1  4
2  5
2  7 
3  10
3  0

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In reply to Re^3: Excel and Perl by wind
in thread Excel and Perl by kb

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