human
A string is called a k-string if it can be represented as k concatenated copies of some string. For example, the string "aabaabaabaab" is at the same time a 1-string, a 2-string and a 4-string, but it is not a 3-string, a 5-string, or a 6-string and so on. Obviously any string is a 1-string.

You are given a string s, consisting of lowercase English letters and a positive integer k. Your task is to reorder the letters in the string s in such a way that the resulting string is a k-string.

Input

The first input line contains integer k (1 ≤ k ≤ 1000). The second line contains s, all characters in s are lowercase English letters. The string length s satisfies the inequality 1 ≤ |s| ≤ 1000, where |s| is the length of string s.

Output

Rearrange the letters in string s in such a way that the result is a k-string. Print the result on a single output line. If there are multiple solutions, print any of them.

If the solution doesn't exist, print "-1" (without quotes).

Examples

Input

2
aazz

Output

azaz

Input

3
abcabcabz

Output

-1
from
assistant
#Here is Python program to print the result on a single output line.
collections import Counter

class Code:
    def __init__(self):
        self.k, self.s = int(input()), input()

    def process(self):
        s, res = list(self.s), ''
        s.sort()
        cnt = Counter(s)
        for k, v in cnt.items():
            res += k * (v // self.k)
        print(res * self.k if len(res) * self.k == len(self.s) else -1)

if __name__ == '__main__':
    code = Code()
    code.process()