#include <iostream>
#include <vector>
#include <math.h>
#include <stdio.h>
#include <algorithm>
#include <string>
#include <map>
#include <queue>
#include <memory.h>
#include <bitset>
using namespace std;

typedef pair<int,int> P;

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