Kolya has a string s of length n consisting of lowercase and uppercase Latin letters and digits. He wants to rearrange the symbols in s and cut it into the minimum number of parts so that each part is a palindrome and all parts have the same lengths . A palindrome is a string which reads the same backward as forward, such as madam or racecar . Your task is to help Kolya and determine the minimum number of palindromes of equal lengths to cut s into, if it is allowed to rearrange letters in s before cuttings. The first line contains an integer n ( 1 ≤ n ≤ 4·10 5 ) — the length of string s . The second line contains a string s of length n consisting of lowercase and uppercase Latin letters and digits. Print to the first line an integer k — minimum number of palindromes into which you can cut a given string. Print to the second line k strings — the palindromes themselves. Separate them by a space. You are allowed to print palindromes in arbitrary order. All of them should have the same length.