#include <iostream>

using namespace std;

int main()
{
	string str; cin >> str;
	
	for (int i = 0; i < str.length(); i++)
	{
		str[i] = (str[i] + 26 - (i % 26) - 1 - 'A') % 26 + 'A';
	}
	
	cout << str << endl;
	
	return 0;
}