B"Vadim is really keen on travelling. Recently he heard about kayaking activity near his town and became very excited about it, so he joined a party of kayakers. Now the party is ready to start its journey, but firstly they have to choose kayaks. There are 2 xc2 xb7n people in the group (including Vadim), and they have exactly n xe2 x80 x89- xe2 x80 x891 tandem kayaks (each of which, obviously, can carry two people) and 2 single kayaks. i-th person's weight is wi, and weight is an important matter in kayaking -- if the difference between the weights of two people that sit in the same tandem kayak is too large, then it can crash. And, of course, people want to distribute their seats in kayaks in order to minimize the chances that kayaks will crash. Formally, the instability of a single kayak is always 0, and the instability of a tandem kayak is the absolute difference between weights of the people that are in this kayak. Instability of the whole journey is the total instability of all kayaks. Help the party to determine minimum possible total instability! The first line contains one number n (2 xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89n xe2 x80 x89 xe2 x89 xa4 xe2 x80 x8950). The second line contains 2 xc2 xb7n integer numbers w1, w2, ..., w2n, where wi is weight of person i (1 xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89wi xe2 x80 x89 xe2 x89 xa4 xe2 x80 x891000). Print minimum possible total instability. "...