#include<iostream>
#include<string>
using namespace std;

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