#include <bits/stdc++.h>
#define rep(i,n)for(long long i=0;i<(n);i++)
using namespace std;
typedef long long ll;
const int MOD=1e9+7;
const int MAX = 510000;
const double pi=acos(-1);

int main(){
  string s;
  cin >> s;
  rep(i,s.size()){
    int num=(i+1)%26;
    if('A'<= char(s[i]-num) &&  char(s[i]-num)<='Z') s[i]=char(s[i]-num);
    else if(char(s[i]-num)<'A') s[i]=char(s[i]-num+26);
    else s[i]=char(s[i]-num-26);
  }
  cout << s << endl;
  return 0;
}