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.

输入描述:

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.

输出描述:

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).