local band = bit.band local FenwickTree = {} FenwickTree.create = function(self, n) self.n = n self.v = {} for i = 1, n do self.v[i] = 0 end end FenwickTree.add = function(self, pos, val) while pos <= self.n do self.v[pos] = self.v[pos] + val pos = pos + band(pos, -pos) end end FenwickTree.sum = function(self, r) local ret = 0 while 0 < r do ret = ret + self.v[r] r = r - band(r, -r) end return ret end FenwickTree.new = function(n) local obj = {} setmetatable(obj, {__index = FenwickTree}) obj:create(n) return obj end local n = io.read("*n") local t = {} for i = 1, n do t[i] = 0 end for i = 1, n do local a = io.read("*n") t[a] = i end local ret = 0 local fw = FenwickTree.new(n) for i = 1, n do local b = io.read("*n") b = t[b] ret = ret + i - 1 - fw:sum(b) fw:add(b, 1) end print(ret)