Problem:
Score : 200 points

Problem Statement

Given are a positive integer N and a string S of length N consisting of lowercase English letters.

Determine whether the string is a concatenation of two copies of some string.
That is, determine whether there is a string T such that S = T + T.

Constraints

1 \leq N \leq 100

S consists of lowercase English letters.

|S| = N

Input

Input is given from Standard Input in the following format:

N
S

Output

If S is a concatenation of two copies of some string, print Yes; otherwise, print No.

Sample Input 1

6
abcabc

Sample Output 1

Yes

Let T = abc, and S = T + T.

Sample Input 2

6
abcadc

Sample Output 2

No

Sample Input 3

1
z

Sample Output 3

No

Solution in Haskell (GHC 8.8.3) (judge verdict: Accepted)

import qualified Data.ByteString.Char8 as BS
import qualified Data.Maybe as Maybe
import qualified Debug.Trace as Trace

solve :: Int -> String -> String
solve x s
    | ((mod x 2) /= 0) = "No"
    | (take (div x 2) s) == (drop (div x 2) s) = "Yes"
    | otherwise = "No"

main = do
    n <- (fst . Maybe.fromJust . BS.readInt) <$> BS.getLine
    s <- getLine
    let ans = solve n s
    putStrLn ans