#include <iostream>

using namespace std;

string S;

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