#include <iostream>
using namespace std;
int main(void) {
	cin.tie(0);
	ios::sync_with_stdio(false);
	
	string s;
	cin >> s;
	for (int i = 0; i < s.size(); ++i) {
		int n = (i + 1) % 26;
		if (s[i] - n >= 65) cout << char (s[i] - n);
		else cout << char (s[i] - n + 26);
	}
	return 0;
}