caesar-cipher-1

Caesar Cipher ⬀

Julius Caesar protected his confidential information by encrypting it using a cipher. Caesar's cipher shifts each letter by a number of letters. If the shift takes you past the end of the alphabet, just rotate back to the front of the alphabet. In the case of a rotation by 3, w, x, y and z would map to z, a, b and c.

Original alphabet:      abcdefghijklmnopqrstuvwxyz
Alphabet rotated +3:    defghijklmnopqrstuvwxyzabc

Example

s = There's-a-starman-waiting-in-the-sky
k = 3

The alphabet is rotated by 3, matching the mapping above. The encrypted string is Wkuh'v-d-vwdupdq-zdlwlqj-lq-wkh-vnb.

Note: The cipher only encrypts letters; symbols, such as -, remain unencrypted.

Function Description

Complete the caesarCipher function in the editor below.

caesarCipher has the following parameter(s):

• string s: cleartext
• int k: the alphabet rotation factor

Returns

• string: the encrypted string

Input Format

• The first line contains the integer, n, the length of the unencrypted string.
• The second line contains the unencrypted string, s.
• The third line contains k, the number of letters to rotate the alphabet by.

Constraints

• 1 ≤ n ≤ 100
• 1 ≤ k ≤ 100
• s is a valid ASCII string without any spaces.

Sample Input

11
middle-Outz
2

Sample Output

okffng-Qwvb

Explanation

Original alphabet:      abcdefghijklmnopqrstuvwxyz
Alphabet rotated +2:    cdefghijklmnopqrstuvwxyzab

m -> o
i -> k
d -> f
d -> f
l -> n
e -> g
-    -
O -> Q
u -> w
t -> v
z -> b