#include <bits/stdc++.h>
using namespace std;

template<typename T>
void fin(T a){
  cout<<a<<endl;
  exit(0);
}

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