#line 2 "/home/sakflat/CP/_library/cpp/template/template.cpp" //yukicoder@cpp17 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; using ll = long long; using P = pair; const ll MOD = 998244353; const ll MODx = 1000000007; const int INF = (1<<30)-1; const ll LINF = (1LL<<62LL)-1; const double EPS = (1e-10); P ar4[4] = {{0,1},{0,-1},{1,0},{-1,0}}; P ar8[8] = {{-1,-1},{-1,0},{-1,1},{0,-1},{0,1},{1,-1},{1,0},{1,1}}; template vector make_vector(size_t a, T b) { return vector(a, b); } template auto make_vector(size_t a, Ts... ts) { return vector(a, make_vector(ts...)); } /* 確認ポイント cout << fixed << setprecision(n) << 小数計算//n桁の小数表記になる 計算量は変わらないが楽できるシリーズ min(max)_element(iter,iter)で一番小さい(大きい)値のポインタが帰ってくる count(iter,iter,int)でintがiterからiterの間にいくつあったかを取得できる */ /* comment outed because can cause bugs __attribute__((constructor)) void initial() { cin.tie(0); ios::sync_with_stdio(false); } */ #line 2 "/home/sakflat/CP/_library/cpp/template/basic.cpp" #line 1 "/home/sakflat/CP/_library/cpp/data-structure/segment-tree/segment-tree.cpp" template< typename T, typename F> struct SegmentTree{ private: int n; vector node; F f; T initer; public: SegmentTree(int n_, F f, T initer) : f(f),initer(initer) { n = 1; while(n < n_)n*=2; node.resize(2*n-1, initer); } SegmentTree(int n_, F f,T initer, vector x) : f(f),initer(initer) { n = 1; while(n < n_)n*=2; node.resize(2*n-1, initer); set(x); } void set(vector x){ for(int i = 0; (int)x.size() > i; i++){ update(i,x[i]); } } void update(int x, T val){ x += (n-1); node[x] = val; while(x > 0){ x = (x-1)/2; node[x] = f(node[2*x+1],node[2*x+2]); } } void add(int x, T val){ x += (n-1); node[x] += val; while(x > 0){ x = (x-1)/2; node[x] = f(node[2*x+1],node[2*x+2]); } } T getf(int a,int b, int k=0, int l=0, int r=-1){ if(r < 0){ r = n-1; } if(r < a || b < l){ return initer; } if(a <= l && r <= b){ return node[k]; } T vl = getf(a,b,2*k+1,l,(l+r)/2); T vr = getf(a,b,2*k+2,(l+r)/2+1,r); return f(vl,vr); } void debug(){ int nw = 1; int curr = 1; cout << "---begin---" << endl; for(int i = 0; 2*n-1 > i; i++){ cout << node[i] << " "; if(nw == curr)cout << endl,nw *= 2, curr=1; else curr++; } cout << "---end---" << endl; } }; template SegmentTree get_segment_tree(int N, const F &f, T initer){ return SegmentTree{N,f,initer}; } template SegmentTree get_segment_tree(int N, const F &f, T initer, vector x){ return SegmentTree{N,f,initer,x}; } int main(){ int n;cin>>n; vector A(n), B(n); vector C; for(int i = 0; n > i; i++){ cin>>A[i]; C.push_back(A[i]); } sort(A.begin(), A.end()); for(int i = 0; n > i; i++){ cin>>B[i]; C.push_back(B[i]); } sort(C.begin(), C.end()); map Cc; for(int i = 0; C.size() > i; i++){ Cc[C[i]] = i+1; } auto seg = get_segment_tree(C.size()+1, [](long long a, long long b){return a+b;}, 0LL); long long ans = 0; for(int i = 0; n > i; i++){ seg.add(Cc[B[i]], 1); ans += seg.getf(0, Cc[A[i]]-1); } cout << ans << endl; return 0; }