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 Python (3.4.3) (judge verdict: Accepted)

import os


def alpha2num(alpha):
    num=0
    for index, item in enumerate(list(alpha)):
        num += pow(26,len(alpha)-index-1)*(ord(item)-ord('A')+1)
    return num

def num2alpha(num):
    if num<=26:
        return chr(64+num)
    elif num%26==0:
        return num2alpha(num//26-1)+chr(90)
    else:
        return num2alpha(num//26)+chr(64+num%26)

def main():
	n = int(input())
	s = input()
	result = ""
	for i in s:
		num = alpha2num(i)
		if num + n > 26:
			num = num + n - 26
		else:
			num += n
		string = num2alpha(num)
		result += string
	print(result)
	

if __name__ == "__main__":
	main()