Problem:
Score : 200 points

Problem Statement

We have a string S consisting of uppercase English letters. Additionally, an integer N will be given.

Shift each character of S by N in alphabetical order (see below), and print the resulting string.

We assume that A follows Z. For example, shifting A by 2 results in C (A \to B \to C), and shifting Y by 3 results in B (Y \to Z \to A \to B).

Constraints

0 \leq N \leq 26

1 \leq |S| \leq 10^4

S consists of uppercase English letters.

Input

Input is given from Standard Input in the following format:

N
S

Output

Print the string resulting from shifting each character of S by N in alphabetical order.

Sample Input 1

2
ABCXYZ

Sample Output 1

CDEZAB

Note that A follows Z.

Sample Input 2

0
ABCXYZ

Sample Output 2

ABCXYZ

Sample Input 3

13
ABCDEFGHIJKLMNOPQRSTUVWXYZ

Sample Output 3

NOPQRSTUVWXYZABCDEFGHIJKLM

Solution in Ruby (2.3.3) (judge verdict: Runtime Error)

num = gets.chomp.to_i
letters = gets.chomp.split('')
a_to_z = [*"A".."Z"]
answer = []
letters.each do |letter|
  if $a_to_z.index(letter) + $num < $a_to_z.count
    $answer << $a_to_z[$a_to_z.index(letter) + $num]
  else
    $answer << $a_to_z[($a_to_z.index(letter) + $num) - $a_to_z.count]
  end 
end
puts $answer.join("")