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

char encrypt(char c, int n)
{
    char ret;
    ret = c - n % 26;
    if (ret < 'A') {
        ret += 'Z' - 'A' + 1;
    }
    return ret;
}

int main()
{
    cin.tie(0)->sync_with_stdio(0);

    string s;
    cin >> s;
    for (int i = 0; i < s.size(); i++) {
        cout << encrypt(s[i], i + 1);
    }
    cout << endl;
}