[ I moved your post to Seekers of Perl Wisdom. Cool Uses for Perl is for showing off interesting or useful pieces of Perl code ]

how to compare them

Compare what to what?

how to [...] print name of the biggest

use strict;
use warnings;
use feature qw( say );

use List::Util qw( reduce );

my %students = ( ... );

my $highest = reduce { $students{$a} >= $students{$b} ? $a : $b }
   keys(%students);

say $students{$highest};
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List::Util, say

Your issue is addressed perlfaq4, though not directly. Take a look at How do I sort an array by (anything)?, How do I process an entire hash? and How do I sort a hash (optionally by value instead of key)?. If you review those articles and are still lost, assembled some code(even if it doesn't work correctly) and post again for further guidance.

Sorting is not necessary to find a maximum.

TIMTOWTDI, and you are literally correct. Given the apparent familiarity of the OP with the subject matter, I was assuming he would benefit more from direction and documentation than from code.

perl -e "my %s=qw |dos 2 cinco 5 Uno 1 cuatro 4 tres 3|;  $s{$_} > $s{
+$h}? $h=$_:0 for keys %s;prin
t $h"
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