struct Scanner {
    private var stack = [String]()
    private var index = 0
    
    mutating func peek() -> String {
        if stack.count == index {
            stack += readLine()!.split(separator: " ").map{ String($0) }
        }
        return stack[index]
    }
    
    mutating func next() -> String {
        let value = peek()
        index += 1
        return value
    }
    
    mutating func nextInt() -> Int {
        return Int(next())!
    }
    
    mutating func nextDouble() -> Double {
        return Double(next())!
    }
}

var scanner = Scanner()
let N = scanner.nextInt()

let A = (0 ..< N).map { _ in scanner.nextInt() - 1 }
let B = (0 ..< N).map { _ in scanner.nextInt() - 1 }

var I = [Int](repeating: 0, count: N)
for i in A.indices {
    I[A[i]] = i
}

struct Counter {
    static let size = 500
    var this = [Int](repeating: 0, count: size * size)
    var these = [Int](repeating: 0, count: size)

    mutating func increment(_ index: Int) {
        this[index] += 1
        these[index / Self.size] += 1
    }
    
    func count(le: Int) -> Int {
        var value = 0
        var k = le
        while k % Self.size != 0 {
            value += this[k]
            k += 1
        }
        k /= Self.size
        while k < Self.size {
            value += these[k]
            k += 1
        }
        return value
    }
}

var counter = Counter()

var answer = 0
for x in B {
    answer += counter.count(le: I[x])
    counter.increment(I[x])
}
print(answer)