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: Runtime Error)

n=int(input())
print(n**2)
#B
n=int(input())
s=list(str(input()))
if n % 2 ==0:
    ans=0
    for i in range(n//2):
        if s[i]==s[n//2+i]:
            ans+=1
        else:
            ans+=0

    if ans==n//2:
        print('Yes')
    else:
        print('No')   

else:
    print('No')