#include"bits/stdc++.h"
using namespace std;
using ll = long long;
using ld = long double;
#define rep(i,m,n) for(ll i=(ll)m;i<(ll)n;i++)
#define Endl endl
#define pr(i,j) make_pair(i,j) 
const ll mod = 998244353;
const ll inf = 5e18;
const ld pi = 3.14159265358979;
int main() {
	string s;
	cin >> s;
	rep(i, 0, s.length()) {
		ll k = s[i] - 'A';
		k -= i + 1;
		k %= 26;
		k += 26;
		k %= 26;
		s[i] = 'A' + (char)k;
	}
	cout << s << endl;
}