#include <stdio.h>

char caesar(char c, int i){
    c -= 'Z'; /* if replace 'Z' to 'A' , it doesn't work */
    c = ( c-i-1 ) % 26;
    c += 'Z';
    return c;
}

int main(){
    int len = 1024;
    char arr[len];
    scanf("%s", arr);
    for(int i=0; i<len; i++){
        if(arr[i] == '\0') break;
        arr[i] = caesar(arr[i], i);
    }
    printf(arr);

    return 0;
}