#include <iostream>
using namespace std;
int main(void){
    // Your code here!
    char s[1025] = {};
    
    cin >> s;
    
    for(int i = 0; s[i] != '\0'; i++) {
        int a = i % 26 + 1;
        if(s[i] == 0)break;
        if((s[i] - a) < 'A'){
            s[i] = s[i] - a + 26;
        } else {
            s[i] = s[i] - a;
        }
        
    }
    
    cout << s;
    
}