#include <bits/stdc++.h>
#define rep(i,n) for(int i=0;i<(n);i++)
#define ALL(A) A.begin(), A.end()

using namespace std;

typedef long long ll;
typedef pair<int, int> P;

int main()
{
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	string s; cin >> s;
	int n = s.length();

	string res = "";
	rep (i, n)
		res += (char)('A' + ((int)(s[i] - 'A') + 40 * 26 - (i+1)) % 26);
	
	cout << res << endl;
	
	return 0;
}