Submission #29476670

---

Source Code Expand

#include <vector>
#include <algorithm>

namespace nachia{

struct WaveletMatrix{
    using u64 = unsigned long long;
    struct WordBlock{ u64 table; int ptr; };
    int n;
    int S;
    int logS;
    ::std::vector<::std::vector<WordBlock>> Table;
  
    int popcount(unsigned long long c){
        return __builtin_popcountll(c);
    }
    WaveletMatrix(int maxVal, ::std::vector<int> A){
        S = 1; logS = 0;
        n = A.size();
        while(S <= maxVal){ S *= 2; logS += 1; }
        Table.resize(logS);
        for(int d=logS-1; d>=0; d--){
            ::std::vector<WordBlock> tableBuf(n/64+2,{0,0});
            for(int i=0; i<n; i++) tableBuf[i/64].table |= (u64)((A[i]>>d) & 1) << (i%64);
            for(int i=1; i<=n/64+1; i++) tableBuf[i].ptr = tableBuf[i-1].ptr + popcount(tableBuf[i-1].table);
            ::std::vector<int> buf;
            for(int b : {0,1<<d}) for(int a : A) if((a&(1<<d))==b) buf.push_back(a);
            ::std::swap(Table[d],tableBuf);
            ::std::swap(A,buf);
        }
    }
    int getLevelRank(int level, int p){
        int res = Table[level][p/64].ptr + popcount(Table[level][p/64].table & ~(~(u64)0 << (p%64)));
        return res;
    }
    int getLeftPointer(int level, int p){
        return p - getLevelRank(level,p);
    }
    int getRightPointer(int level, int p){
        return n - Table[level].back().ptr + getLevelRank(level,p);
    }
    int get(int p){
        int res = 0;
        for(int d=logS-1; d>=0; d--){
            res *= 2;
            if(Table[d][p/64].table & ((u64)1 << (p%64))){
                res |= 1;
                p = getRightPointer(d,p);
            }
            else{
                p = getLeftPointer(d,p);
            }
        }
        return res;
    }
    int count(int l, int r, int val){
        for(int d=logS-1; d>=0; d--){
            if(val & (1<<d)){
                l = getRightPointer(d,l);
                r = getRightPointer(d,r);
            }
            else{
                l = getLeftPointer(d,l);
                r = getLeftPointer(d,r);
            }
        }
        return r - l;
    }
    int getKthSmallest(int l, int r, int k){
        int res = 0;
        for(int d=logS-1; d>=0; d--){
            res *= 2;
            int zerocnt = r - l;
            zerocnt -= getLevelRank(d,r);
            zerocnt += getLevelRank(d,l);
            if(k < zerocnt){
                l = getLeftPointer(d,l);
                r = getLeftPointer(d,r);
            }
            else{
                res += 1;
                k -= zerocnt;
                l = getRightPointer(d,l);
                r = getRightPointer(d,r);
            }
        }
        return res;
    }
};


} // namespace nachia


#include <vector>
#include <algorithm>


#include <utility>

namespace nachia{
    
struct AdjacencyList{
public:
    struct AdjacencyListRange{
        using iterator = typename std::vector<int>::const_iterator;
        iterator begi, endi;
        iterator begin() const { return begi; }
        iterator end() const { return endi; }
        int size() const { return (int)std::distance(begi, endi); }
        const int& operator[](int i) const { return begi[i]; }
    };
private:
    int mn;
    std::vector<int> E;
    std::vector<int> I;
public:
    AdjacencyList(int n, std::vector<std::pair<int,int>> edges, bool rev){
        mn = n;
        std::vector<int> buf(n+1, 0);
        for(auto [u,v] : edges){ ++buf[u]; if(rev) ++buf[v]; }
        for(int i=1; i<=n; i++) buf[i] += buf[i-1];
        E.resize(buf[n]);
        for(int i=(int)edges.size()-1; i>=0; i--){
            auto [u,v] = edges[i];
            E[--buf[u]] = v;
            if(rev) E[--buf[v]] = u;
        }
        I = std::move(buf);
    }
    AdjacencyList(const std::vector<std::vector<int>>& edges = {}){
        int n = mn = edges.size();
        std::vector<int> buf(n+1, 0);
        for(int i=0; i<n; i++) buf[i+1] = buf[i] + edges[i].size();
        E.resize(buf[n]);
        for(int i=0; i<n; i++) for(int j=0; j<(int)edges[i].size(); j++) E[buf[i]+j] = edges[i][j];
        I = std::move(buf);
    }
    static AdjacencyList from_raw(std::vector<int> targets, std::vector<int> bounds){
        AdjacencyList res;
        res.mn = bounds.size() - 1;
        res.E = std::move(targets);
        res.I = std::move(bounds);
        return res;
    }
    AdjacencyListRange operator[](int u) const {
        return AdjacencyListRange{ E.begin() + I[u], E.begin() + I[u+1] };
    }
    int num_vertices() const { return mn; }
    int num_edges() const { return E.size(); }
    AdjacencyList reversed_edges() const {
        AdjacencyList res;
        int n = res.mn = mn;
        std::vector<int> buf(n+1, 0);
        for(int v : E) ++buf[v];
        for(int i=1; i<=n; i++) buf[i] += buf[i-1];
        res.E.resize(buf[n]);
        for(int u=0; u<n; u++) for(int v : operator[](u)) res.E[--buf[v]] = u;
        res.I = std::move(buf);
        return res;
    }
};

struct AdjacencyListEdgeIndexed{
public:
    struct Edge { int to; int edgeidx; };
    struct AdjacencyListRange{
        using iterator = typename std::vector<Edge>::const_iterator;
        iterator begi, endi;
        iterator begin() const { return begi; }
        iterator end() const { return endi; }
        int size() const { return (int)std::distance(begi, endi); }
        const Edge& operator[](int i) const { return begi[i]; }
    };
private:
    int mn;
    std::vector<Edge> E;
    std::vector<int> I;
public:
    AdjacencyListEdgeIndexed(int n, const std::vector<std::pair<int,int>>& edges, bool rev){
        mn = n;
        std::vector<int> buf(n+1, 0);
        for(auto [u,v] : edges){ ++buf[u]; if(rev) ++buf[v]; }
        for(int i=1; i<=n; i++) buf[i] += buf[i-1];
        E.resize(buf[n]);
        for(int i=(int)edges.size()-1; i>=0; i--){
            auto [u,v] = edges[i];
            E[--buf[u]] = { v, i };
            if(rev) E[--buf[v]] = { u, i };
        }
        I = std::move(buf);
    }
    AdjacencyListEdgeIndexed() : AdjacencyListEdgeIndexed(0, {}, false) {}
    AdjacencyListRange operator[](int u) const {
        return AdjacencyListRange{ E.begin() + I[u], E.begin() + I[u+1] };
    }
    int num_vertices() const { return mn; }
    int num_edges() const { return E.size(); }
    AdjacencyListEdgeIndexed reversed_edges() const {
        AdjacencyListEdgeIndexed res;
        int n = res.mn = mn;
        std::vector<int> buf(n+1, 0);
        for(auto [v,i] : E) ++buf[v];
        for(int i=1; i<=n; i++) buf[i] += buf[i-1];
        res.E.resize(buf[n]);
        for(int u=0; u<n; u++) for(auto [v,i] : operator[](u)) res.E[--buf[v]] = {u,i};
        res.I = std::move(buf);
        return res;
    }
};

} // namespace nachia

namespace nachia{

struct HeavyLightDecomposition{
private:

    int N;
    std::vector<int> P;
    std::vector<int> PP;
    std::vector<int> PD;
    std::vector<int> D;
    std::vector<int> I;

    std::vector<int> rangeL;
    std::vector<int> rangeR;

public:

    HeavyLightDecomposition(const AdjacencyList& E = AdjacencyList(1, {}, false)){
        N = E.num_vertices();
        P.assign(N, -1);
        I = {0};
        I.reserve(N);
        for(int i=0; i<(int)I.size(); i++){
            int p = I[i];
            for(int e : E[p]) if(P[p] != e){
                I.push_back(e);
                P[e] = p;
            }
        }
        std::vector<int> Z(N, 1);
        std::vector<int> nx(N, -1);
        PP.resize(N);
        for(int i=0; i<N; i++) PP[i] = i;
        for(int i=N-1; i>=1; i--){
            int p = I[i];
            Z[P[p]] += Z[p];
            if(nx[P[p]] == -1) nx[P[p]] = p;
            if(Z[nx[P[p]]] < Z[p]) nx[P[p]] = p;
        }

        for(int p : I) if(nx[p] != -1) PP[nx[p]] = p;

        PD.assign(N,N);
        PD[0] = 0;
        D.assign(N,0);
        for(int p : I) if(p != 0){
            PP[p] = PP[PP[p]];
            PD[p] = std::min(PD[PP[p]], PD[P[p]]+1);
            D[p] = D[P[p]]+1;
        }
        
        rangeL.assign(N,0);
        rangeR.assign(N,0);
        std::vector<int> dfs;
        dfs.push_back(0);
        while(dfs.size()){
            int p = dfs.back();
            rangeR[p] = rangeL[p] + Z[p];
            int ir = rangeR[p];
            dfs.pop_back();
            for(int e : E[p]) if(P[p] != e) if(e != nx[p]){
                rangeL[e] = (ir -= Z[e]);
                dfs.push_back(e);
            }
            if(nx[p] != -1){
                rangeL[nx[p]] = rangeL[p] + 1;
                dfs.push_back(nx[p]);
            }
        }

        I.resize(N);
        for(int i=0; i<N; i++) I[rangeL[i]] = i;
    }

    int depth(int p) const { return D[p]; }
    int to_seq(int vertex) const { return rangeL[vertex]; }
    int to_vtx(int seqidx) const { return I[seqidx]; }
    int parent_of(int v) const { return P[v]; }
    int heavy_child_of(int v) const {
        if(to_seq(v) == N-1) return -1;
        int cand = to_vtx(to_seq(v) + 1);
        if(PP[v] == PP[cand]) return cand;
        return v;
    }

    int lca(int u, int v) const {
        if(PD[u] < PD[v]) std::swap(u, v);
        while(PD[u] > PD[v]) u = P[PP[u]];
        while(PP[u] != PP[v]){ u = P[PP[u]]; v = P[PP[v]]; }
        return (D[u] > D[v]) ? v : u;
    }

    int dist(int u, int v) const {
        return depth(u) + depth(v) - depth(lca(u,v)) * 2;
    }

    std::vector<std::pair<int,int>> path(int r, int c, bool include_root = true, bool reverse_path = false) const {
        if(PD[c] < PD[r]) return {};
        std::vector<std::pair<int,int>> res(PD[c]-PD[r]+1);
        for(int i=0; i<(int)res.size()-1; i++){
            res[i] = std::make_pair(rangeL[PP[c]], rangeL[c]+1);
            c = P[PP[c]];
        }
        if(PP[r] != PP[c] || D[r] > D[c]) return {};
        res.back() = std::make_pair(rangeL[r]+(include_root?0:1), rangeL[c]+1);
        if(res.back().first == res.back().second) res.pop_back();
        if(!reverse_path) std::reverse(res.begin(),res.end());
        else for(auto& a : res) a = std::make_pair(N - a.second, N - a.first);
        return move(res);
    }

    std::pair<int,int> subtree(int p){
        return std::make_pair(rangeL[p], rangeR[p]);
    }

    int median(int x, int y, int z) const {
        return lca(x,y) ^ lca(y,z) ^ lca(x,z);
    }

    int la(int from, int to, int d) const {
        if(d < 0) return -1;
        int g = lca(from,to);
        int dist0 = D[from] - D[g] * 2 + D[to];
        if(dist0 < d) return -1;
        int p = from;
        if(D[from] - D[g] < d){ p = to; d = dist0 - d; }
        while(D[p] - D[PP[p]] < d){
            d -= D[p] - D[PP[p]] + 1;
            p = P[PP[p]];
        }
        return I[rangeL[p] - d];
    }
};

} // namespace nachia




#include <vector>
#include <algorithm>

namespace nachia{

class CoordinateCompress {
    using Elem = long long;
    static const Elem negInf = -1001001001001001001;
    std::vector<std::pair<Elem, int>> G;
    std::vector<int> res;
    std::vector<Elem> mRealval;
    Elem mMaxcoord;
    bool ok = true;
    void calc() {
        if (ok) return;
        sort(G.begin(), G.end());
        res.resize(G.size());
        mRealval.clear();
        Elem x = negInf;
        int p = -1;
        for(int i=0; i<(int)G.size(); i++){
            if (x != G[i].first) { x = G[i].first; mRealval.push_back(x); p++; }
            res[G[i].second] = p;
        }
        mMaxcoord = p;
        ok = true;
    }
public:
    int push(Elem x) {
        ok = false;
        G.push_back({ x,(int)G.size() });
        return G.back().second;
    }
    int operator[](int i) {
        calc();
        return res[i];
    }
    Elem realval(int x) {
        calc();
        return mRealval[x];
    }
    Elem maxcoord() {
        calc();
        return mMaxcoord;
    }
};

template<class Elem>
std::vector<int> coordinate_compress_instant(const std::vector<Elem>& A, bool disjoint = false){
    int n = A.size();
    std::vector<int> ord(n);
    for(int i=0; i<n; i++) ord[i] = i;
    if(disjoint){
        std::sort(ord.begin(), ord.end(), [&](int l, int r) -> bool { return (A[l] != A[r]) ? (A[l] < A[r]) : (l < r); });
        std::vector<int> res(n, 0);
        for(int i=0; i<n; i++) res[ord[i]] = i;
        return res;
    }
    std::sort(ord.begin(), ord.end(), [&](int l, int r) -> bool { return A[l] < A[r]; });
    std::vector<int> res(n, 0);
    for(int i=1; i<n; i++) res[ord[i]] = res[ord[i-1]] + ((A[ord[i-1]] < A[ord[i]]) ? 1 : 0);
    return res;
}

} // namespace nachia



#include <iostream>
#include <atcoder/modint>
using namespace std;
using i64 = long long;
#define rep(i,n) for(int i=0; i<(int)(n); i++)
using modint = atcoder::static_modint<998244353>;

int main(){
    int N; cin >> N;
    int Q; cin >> Q;
    vector<int> X(N);
    nachia::CoordinateCompress CCX;

    rep(i,N){
        int x; cin >> x;
        X[i] = CCX.push(x);
    }
    rep(i,N) X[i] = CCX[X[i]]; // 座標圧縮 完了

    vector<pair<int,int>> edges;
    rep(i,N-1){ int u,v; cin >> u >> v; edges.push_back({u-1,v-1}); }

    // オイラーツアー
    nachia::HeavyLightDecomposition hld(nachia::AdjacencyList(N, edges, true));

    // 座標圧縮したものを元に wavelet matrix を構築
    vector<int> XX(N);
    rep(i,N) XX[i] = X[hld.to_vtx(i)];
    auto rq = nachia::WaveletMatrix(N, XX);

    rep(q,Q){
        int v,k; cin >> v >> k; v--;
        auto w = hld.subtree(v); // 部分木が対応する区間を取得
        k = w.second - w.first - k; // k-th smallest に変換
        int ans = rq.getKthSmallest(w.first, w.second, k); // クエリ
        ans = CCX.realval(ans); // 座標圧縮の復元
        cout << ans << '\n';
    }

    return 0;
}




struct ios_do_not_sync{
    ios_do_not_sync(){
        std::ios::sync_with_stdio(false);
        std::cin.tie(nullptr);
    }
} ios_do_not_sync_instance;

Submission Info

Compile Error

./Main.cpp: In member function ‘std::vector<std::pair<int, int> > nachia::HeavyLightDecomposition::path(int, int, bool, bool) const’:
./Main.cpp:324:20: warning: moving a local object in a return statement prevents copy elision [-Wpessimizing-move]
  324 |         return move(res);
      |                ~~~~^~~~~
./Main.cpp:324:20: note: remove ‘std::move’ call

Judge Result