#include #define rep(i,n) for(int i=(0);i<(n);i++) using namespace std; typedef long long ll; template bool chmax(T &a, const T &b) { if (a bool chmin(T &a, const T &b) { if (a>b) { a=b; return 1; } return 0; } template< typename Monoid > struct SegmentTree { using F = function< Monoid(Monoid, Monoid) >; int sz; vector< Monoid > seg; const F f; const Monoid M1; SegmentTree(int n, const F f, const Monoid &M1) : f(f), M1(M1) { sz = 1; while(sz < n) sz <<= 1; seg.assign(2 * sz, M1); } void set(int k, const Monoid &x) { seg[k + sz] = x; } void build() { for(int k = sz - 1; k > 0; k--) { seg[k] = f(seg[2 * k + 0], seg[2 * k + 1]); } } void update(int k, const Monoid &x) { k += sz; seg[k] = x; while(k >>= 1) { seg[k] = f(seg[2 * k + 0], seg[2 * k + 1]); } } Monoid query(int a, int b) { Monoid L = M1, R = M1; for(a += sz, b += sz; a < b; a >>= 1, b >>= 1) { if(a & 1) L = f(L, seg[a++]); if(b & 1) R = f(seg[--b], R); } return f(L, R); } Monoid operator[](const int &k) const { return seg[k + sz]; } }; int main(){ cin.tie(0); ios::sync_with_stdio(false); int n; cin >> n; vector a(n), b(n); rep(i, n) cin >> a[i]; rep(i, n) cin >> b[i]; map mp; rep(i, n) mp[a[i]] = i + 1; SegmentTree seg(n+1, [](int a, int b){ return a + b; }, 0); int ans = 0; rep(i, n){ int j = mp[b[i]]; int val = seg.query(1,j+1); ans += i - val; seg.update(j, 1); } cout << ans << endl; }