#include <cstdio>
#include <algorithm>
#include <vector>
#include <string>
#include <cstring>
#include <iostream>

int main()
{
	using namespace std;

	string s;
	vector<char> ans;

	cin >> s;
	for (int i = 0; i < s.size(); i++)
	{
		int number = (s[i] - 'A' - (i % 26) + 26 - 1) % 26;
		ans.push_back('A' + number);
		//ans.push_back(s.c_str()[i] - (i + 1));
	}
	for (int i = 0; i < ans.size(); i++)
	{
		printf("%c", ans[i]);
	}
	printf("\n");
}