Given a string containing characters as integers only. We need to delete all character of this string in a minimum number of steps where in one step we can delete the substring which is a palindrome. After deleting a substring remaining parts are concatenated.
The first line of input contains an integer T denoting the number of test cases. Then T test cases follow. The first line of each test case contains an integer N denoting the length of the string.
The second line of each test case contains the string consisting of only integer characters.
Count the minimum number of steps to delete the whole string and output the answer in a new line.
1<= T <=100
1<= N <=1000