import std.stdio, std.string, std.conv, std.algorithm, std.numeric;
import std.range, std.array, std.math, std.typecons, std.container, core.bitop;

void main() {
    readln.chomp.enumerate(1).map!(a => cast(char)(((a.value - 'A' - a.index + 26*1024) % 26 + 'A'))).to!string.writeln;
}