Problem Statement

You are given a string S of length N consisting of lowercase English letters.
We denote the i-th character of S by S_i.
Print the string of length 2N obtained by concatenating $S_1,S_1,S_2,S_2,\dots,S_N$, and S_N in this order.
For example, if S is beginner, print bbeeggiinnnneerr.

Input

The input is given from Standard Input in the following format:
N
S

Output

Print the answer.

Constraints

• N is an integer such that $1 \le N \le 50$.
• S is a string of length N consisting of lowercase English letters.

Sample Input 1

8
beginner

Sample Output 1

bbeeggiinnnneerr

It is the same as the example described in the problem statement.

Sample Input 2

3
aaa

Sample Output 2

aaaaaa

见题面 Input 部分

见题面 Output 部分