Sort Lowercase Letters

Given N lowercase letters, sort them in lexicographical order and output the combined string.

For example, if N = 4 and the letters provided are c, d, a, c, then after sorting the concatenated string is: accd.

inputFormat

The first line of the input contains a single integer N denoting the number of lowercase letters. The second line contains N lowercase letters separated by spaces.

outputFormat

Output a single line containing the sorted string formed by concatenating the letters in lexicographical order.

sample

4
c d a c

accd