#include <bits/stdc++.h>

using namespace std;
#define rep(i,n) for(int i=0;i<n;i++)
#define rep1(i,n) for(int i=1;i<=n;i++)
typedef long long ll;

int main(){
  string s;
  cin >> s;
  rep(i,s.size()){
    if(s[i]-(i+1)<65)
      s[i]=s[i]-(i+1)+26;
    else
      s[i]=s[i]-(i+1);
    }
    cout << s << endl;
}