B"You are given an array a with n non-negative integers. You can apply the following operation on it. Find any sequence of at most n operations that makes a non-decreasing. It can be proven that it is always possible. Note that you do not have to minimize the number of operations. An array a_1, a_2, ldots, a_n is non-decreasing if and only if a_1 <= a_2 <= ldots <= a_n . The first line contains one integer t ( 1 <= t <= 10^5 ) -- the number of test cases. Each test case consists of two lines. The first line of each test case contains one integer n ( 1 <= n <= 10^5 ) -- the length of the array. The second line of each test case contains n integers a_1, a_2, ldots, a_n ( 0 <= a_i <= 10^9 ) -- the array itself. It is guaranteed that the sum of n over all test cases doesn't exceed 10^5 . For each test case, print one integer m ( 0 <= m <= n ), the number of operations, in the first line. Then print m lines. Each line must contain two integers l_i, r_i , which are the indices you chose in the i -th operation ( 1 <= l_i < r_i <= n ). If there are multiple solutions, print any of them. In the second test case, a changes like this: In the first and third test cases, a is already non-decreasing. "...