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 C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            var n = int.Parse(Console.ReadLine());
            var list = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".ToCharArray().ToList();
            var shiftList = Shift(list, n).ToList();

            var dict = list.Select((ch, index) => new { ch, index })
                .ToDictionary(s => s.ch, s => shiftList[s.index]);

            var array = Console.ReadLine().ToCharArray().Select(s => dict[s]).ToArray();
            Console.WriteLine(new string(array));
        }

        private static IEnumerable<char> Shift(List<char> list, int n)
        {
            var count = list.Count;
            for (int i = 0; i < count; i++)
            {
                yield return i + n < count ? list[n + i] : list[n + i - count];
            }
        }
    }
}