import std.algorithm, std.conv, std.range, std.stdio, std.string; void main() { char[] s = readln.chomp.dup; foreach (int i, ref c; s) { int d = c - 'A'; d = (d - (i + 1) + 26 * 50) % 26; c = (d + 'A').to!char; } writeln(s); }