B'There is an infinite sequence consisting of all positive integers in the increasing order: p xe2 x80 x89= xe2 x80 x89{1, xe2 x80 x892, xe2 x80 x893, xe2 x80 x89...}. We performed n swap operations with this sequence. A swap(a, xe2 x80 x89b) is an operation of swapping the elements of the sequence on positions a and b. Your task is to find the number of inversions in the resulting sequence, i.e. the number of such index pairs (i, xe2 x80 x89j), that i xe2 x80 x89< xe2 x80 x89j and pi xe2 x80 x89> xe2 x80 x89pj. The first line contains a single integer n (1 xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89n xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89105) -- the number of swap operations applied to the sequence. Each of the next n lines contains two integers ai and bi (1 xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89ai, xe2 x80 x89bi xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89109, ai xe2 x80 x89 xe2 x89 xa0 xe2 x80 x89bi) -- the arguments of the swap operation. Print a single integer -- the number of inversions in the resulting sequence. In the first sample the sequence is being modified as follows: . It has 4 inversions formed by index pairs (1, xe2 x80 x894), (2, xe2 x80 x893), (2, xe2 x80 x894) and (3, xe2 x80 x894).'...