Prefix goodness of a set string is length of longest common prefix*number of strings in the set. For example the prefix goodness of the set {000,001,0011} is 6.You are given a set of binary strings. Find the maximum prefix goodness among all possible subsets of these binary strings. Input First line of the input contains T (≤ 20) the number of test cases. Each of the test cases start with n (≤ 50000) the number of strings. Each of the next n lines contains a string containing only ‘0’ and ‘1’. Maximum length of each of these string is 200. Output For each test case output the maximum prefix goodness among all possible subsets of n binary strings. Sample Input 4 4 0000 0001 10101 010 2 01010010101010101010 11010010101010101010 3 010101010101000010001010 010101010101000010001000 010101010101000010001010 5 01010101010100001010010010100101 01010101010100001010011010101010 00001010101010110101 0001010101011010101 00010101010101001 Sample Output 6 20 66 44