package main

import (
	"bufio"
	"fmt"
	"os"
)

func main() {
	S := nextLine()
	fmt.Println(woosarCipher(S))
}

func woosarCipher(plain string) string {
	cipher := make([]rune, len(plain))
	for i, c := range plain {
		cipher[i] = rotate(c, i+1)
	}
	return string(cipher)
}

func rotate(c rune, n int) rune {
	ret := c - rune(n%26)
	if ret < 'A' {
		return ret + 26
	} else {
		return ret
	}
}

var sc = bufio.NewScanner(os.Stdin)

func nextLine() string {
	sc.Split(bufio.ScanLines)
	sc.Scan()
	if nil != sc.Err() {
		panic(sc.Err())
	}
	return sc.Text()
}