#include <bits/stdc++.h>

using namespace std;

char rotate(char c, int r) {
	return (c - 'A' - r%26 + 26) % 26 + 'A';
}
int main() {
	string s; cin >> s;
	for (int i = 0; i < s.size(); ++i) {
		s[i] = rotate(s[i], i+1);
	}
	cout << s << endl;
}