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 Python (3.4.3) (judge verdict: Accepted)

n = int(input())
s = list(input())
t_1 = list()
t_2 = list()
m = 1
if n % 2 == 0:
    for i in range(int(n / 2)):
        t_1.append(s[i])
        t_2.append(s[int(n / 2) + i])
else:
    m *= 0
    
for i in range(len(t_1)):
    if t_1[i] == t_2[i]:
        m *= 1
    else:
        m *= 0
        break
    
if m == 0:
    print("No")
else:
    print("Yes")