#!/usr/bin/perl

use strict;
use warnings;

my @array = ('A'..'Z');
my $s = <>;
chomp $s;
my @str = split //, $s;
my $change;

for(my $i = 0; $i <length $s; $i++) {
	my $j;
	for($j = 0; $j < 26; $j++) {
		if($str[$i] eq $array[$j]) {
			last;
		}
	}
	$change = $j - ($i % 26) - 1;
	if($change < 0) {
		$change += 26;
	}
	$str[$i] = $array[$change];
}

print @str;
print "\n";
exit;