#include <bits/stdc++.h> 

using i64 = long long; 
using u64 = unsigned long long; 
using u32 = unsigned; 

using u128 = unsigned __int128; 
using i128 = __int128; 

void solve() {
	std::string S; 
	std::cin >> S;

	int n = S.size();

	for(int i = 0; i < n; i ++) {
		int temp = i + 1;
		while(temp --) {
			if(S[i] == 'A') {
				S[i] = 'Z';
			}else S[i]--;
		}
	}

	std::cout << S;
} 

int main() { 
	std::ios::sync_with_stdio(false); 
	std::cin.tie(nullptr); 

	int T = 1; 
	//std::cin >> T; 

	while (T--) { 
		solve(); 
	} 
	return 0; 
}