#include <iostream>
using namespace std;

int main(){
	char c[1024];
	cin >> c;
	for(int i=0;c[i]!='\0';i++){
		c[i]=c[i]-i-1;
		while(c[i]<'A') c[i]+=26;
	}
	cout << c << endl;
	return 0;
}