#include <iostream>
using namespace std;

string S;

void Solve() {
    for (int i = 0; i < S.size(); i++) {
        int offset = (S[i] - 'A' - (i + 1) + 26 * 1024) % 26;
        cout << static_cast<char>('A' + offset);
    }
    cout << endl;
}

int main() {
    cin >> S;

    Solve();

    return 0;
}