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)

'use strict';
 
process.stdin.resume();
process.stdin.setEncoding('utf-8');
 
let inputString = '';
let currentLine = 0;
 
process.stdin.on('data', function(inputStdin) {
    inputString += inputStdin;
});
 
process.stdin.on('end', function() {
    inputString = inputString.split('\n');
    main();
});
 
function readline() {
    return inputString[currentLine++];
}
 
// main funtion .. code start ..... ///
function main() {
 
    var T = parseInt(readline());
    var str = readline();
    
    var res1 = str.slice(0, Math.floor(T/2));
    var res2 = str.slice(T/2);
    
    if(str.length === 1 ) console.log('No');
    else console.log(res1 === res2 ? 'Yes': 'No');
 
}