B"Let's define f(x) for a positive integer x as the length of the base-10 representation of x without leading zeros. I like to call it a digital logarithm. Similar to a digital root, if you are familiar with that. You are given two arrays a and b , each containing n positive integers. In one operation, you do the following: Two arrays are considered similar to each other if you can rearrange the elements in both of them, so that they are equal (e. xe2 x80 x89g. a_i = b_i for all i from 1 to n ). What's the smallest number of operations required to make a and b similar to each other? The first line contains a single integer t ( 1 <= t <= 10^4 ) -- the number of testcases. The first line of the testcase contains a single integer n ( 1 <= n <= 2 cdot 10^5 ) -- the number of elements in each of the arrays. The second line contains n integers a_1, a_2, ... , a_n ( 1 <= a_i < 10^9 ). The third line contains n integers b_1, b_2, ... , b_n ( 1 <= b_j < 10^9 ). The sum of n over all testcases doesn't exceed 2 cdot 10^5 . For each testcase, print the smallest number of operations required to make a and b similar to each other. In the first testcase, you can apply the digital logarithm to b_1 twice. In the second testcase, the arrays are already similar to each other. In the third testcase, you can first apply the digital logarithm to a_1 , then to b_2 . "...