Laurent, use strict; would have caught your typo. I prefer to get the special cases out of the way early. 
use strict;
use warnings;
my ($min, $max) = (0, 0);
while(<DATA>){
    chomp( my $input = $_ );
    last if $input eq '';
    
    $min = $input if $input < $min;
    $max = $input if $input > $max;
}
print "Min and Max are : $min $max \n";
__DATA__
11
13
56
75
53
68
89
22

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Bill

In reply to Re^2: storage of numbers by BillKSmith
in thread storage of numbers by ostra

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