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#include <iostream>
#include <conio.h>
#include <string>
#include <math.h>
#include <algorithm>
#include <vector>
#include <set>
#include <sstream>

using namespace std;

int main()
{
    string s, answer = "";

    cin >> s;

    int prom;
    if (s[0] >= 'A'&& s[0] <= 'Z')
    {
        prom = s[0] - 65;
        if (prom - 5 < 0)
            answer += s[0] + 21;
        else
            answer += s[0] - 5;
    }
    else
    {
        prom = s[0] - 97;
        if (prom - 5 < 0)
            answer += s[0] + 21;
        else
            answer += s[0] - 5;
    }
    for (int i = 1; i <= s.size() - 1; i++)
    {
        if (s[i] >= 'A'&& s[i] <= 'Z')
        {
            if (s[i] - prom < 65)
                answer += s[i] - prom + 26;
            else
                answer += s[i] - prom;
            prom = s[i] - 65;
        }
        else
        {
            if (s[i] - prom < 97)
                answer += s[i] - prom + 26;
            else
                answer += s[i] - prom;
            prom = s[i] - 97;
        }

    }

    cout << answer;

    return 0;
}