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

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