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)

N = int(input())
S = input()

al = [chr(i) for i in range(65, 65+26)]
res_list = []
for s in S:
    tidx = al.index(s)
    if 0 <= tidx+N <=25:
        # print(al[tidx+N])
        res_list.append(al[tidx+N])
    else:
        # print(al[abs(25-(tidx+N)) - 1])
        res_list.append(al[abs(25-(tidx+N)) - 1])
print(''.join(res_list))