#!/usr/bin/perl
use warnings;
use strict;
use Tk;

my $mw = new MainWindow;

my %button;

foreach my $num (0..9){
        
        $button{$num} = $mw -> Button(
         -text => $num,
         -background => 'grey',
         -width => 5,
         -height => 2,
    #    -command => $number=$number==0||$equals!=0?$input:$number.$in
+put,
         -command => sub{
        print "$num\n"; 
        #do whatever here
     }
    
    ) -> pack();
}
MainLoop;
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