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.

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.

Constraints

• $1 \leq N \leq 100$
• S consists of lowercase English letters.
• |S| = N

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

见题面 Input 部分

见题面 Output 部分