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 JavaScript (node.js v5.12) (judge verdict: Accepted)

const fs = require('fs')
const main = (input) => {
    const inputs = input.split("\n");
    const N = Number(inputs[0]);
    const S = inputs[1];
    if (N % 2 !== 0) {
        console.log("No");
    } else {
        console.log(S.slice(0, N/2) === S.slice(N/2, S.length) ? "Yes": "No");
    }
}
main(fs.readFileSync('/dev/stdin', 'utf8'))