package main

import . "fmt"

func main() {
	var x int=1
	for {
		var c rune
		Scanf("%c",&c)
		if c<'A' {
			Println()
			return
		}
		const r='Z'-'A'+1
		c=rune((int(c)-'A'+(r+1-x%(r+1)))%(r+1)+'A')
		Print(string(c))
		x++
	}
}