#include <iostream> #include <vector> #include <cstdio> #include <sstream> #include <map> #include <string> #include <algorithm> #include <queue> #include <cmath> #include <set> using namespace std; int main(){ string s; cin >> s; for(int i=0; i<s.size(); i++){ s[i] = (s[i]-'A'-(i+1)%26+26)%26 + 'A'; } cout << s << endl; return 0; }