#include <iostream>
#include <string>
#include <cstring>
#include <vector>
#include <algorithm>
#define rep(i, x) for(int (i) = 0; (i) < (x); (i) ++)
#define MOD 1000000007
using namespace std;
int main(){

	string s;
	cin >> s;
	rep(i, s.length()){
		if(s[i] - 'A' < (i + 1) % 26){
			s[i] += 26;
		}
		s[i] -= (i + 1) % 26;
	}
	cout << s << endl;

	return 0;
}