B'Let 's denote a k -step ladder as the following structure: exactly k + 2 wooden planks, of which Note that neither the base planks, nor the steps planks are required to be equal. For example, ladders 1 and 3 are correct 2 -step ladders and ladder 2 is a correct 1 -step ladder. On the first picture the lengths of planks are [3, 3] for the base and [1] for the step. On the second picture lengths are [3, 3] for the base and [2] for the step. On the third picture lengths are [3, 4] for the base and [2, 3] for the steps. You have n planks. The length of the i -th planks is a_i . You don 't have a saw, so you can 't cut the planks you have. Though you have a hammer and nails, so you can assemble the improvised "ladder" from the planks. The question is: what is the maximum number k such that you can choose some subset of the given planks and assemble a k -step ladder using them? The first line contains a single integer T ( 1 <= T <= 100 ) -- the number of queries. The queries are independent. Each query consists of two lines. The first line contains a single integer n ( 2 <= n <= 10^5 ) -- the number of planks you have. The second line contains n integers a_1, a_2, ... , a_n ( 1 <= a_i <= 10^5 ) -- the lengths of the corresponding planks. It 's guaranteed that the total number of planks from all queries doesn 't exceed 10^5 . Print T integers -- one per query. The i -th integer is the maximum number k , such that you can choose some subset of the planks given in the i -th query and assemble a k -step ladder using them. Print 0 if you can 't make even 1 -step ladder from the given set of planks. Examples for the queries 1-3 are shown at the image in the legend section. The Russian meme to express the quality of the ladders: '...