Submission #1082569

#	Time	Username	Problem	Language	Result	Execution time	Memory
1082569		Whisper	Roadside Advertisements (NOI17_roadsideadverts)	C++17	100 / 100	50 ms	26708 KiB

roadsideadverts

#include <bits/stdc++.h>

using namespace std;
using ll = long long;

#define int long long
#define FOR(i, a, b) for (int i = (a); i <= (b); i++)
#define FORD(i, a, b) for (int i = (b); i >= (a); i --)
#define REP(i, a) for (int i = 0; i < (a); ++i)
#define REPD(i, a) for (int i = (a) - 1; i >= 0; --i)

#define MASK(i) (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1)


constexpr ll LINF = (1ll << 60);
constexpr int INF = (1ll << 30);
constexpr int Mod = 1e9 + 7;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

/*
    Phu Trong from Nguyen Tat Thanh High School for gifted student
*/

template <class X, class Y>
    bool minimize(X &x, const Y &y){
        X eps = 1e-9;
        if (x > y + eps) {x = y; return 1;}
        return 0;
    }

template <class X, class Y>
    bool maximize(X &x, const Y &y){
        X eps = 1e-9;
        if (x + eps < y) {x = y; return 1;}
        return 0;
    }
#define MIN_HIGH(u, v)          (depth[u] < depth[v] ? (u) : (v))
#define LOG                     20
#define MAX                     50005
int numNode, numQuery;
struct Edge{
    int u, v, w;
    Edge(){}
    Edge(int _u, int _v, int _w): u(_u), v(_v), w(_w){}

    int other(int x){
        return (x ^ u ^ v);
    }
} edge[MAX];
vector<int> G[MAX];

namespace DistanceOnTree{
    int tin[MAX], timeDfs = 0, rev[MAX];

    int cnt = 0, st[MAX << 1][20], pos[MAX << 1], d[MAX], depth[MAX];
    void pre_dfs(int u, int p = -1){
        tin[u] = ++timeDfs; rev[timeDfs] = u;

        st[++cnt][0] = u; pos[u] = cnt;

        for (int&i : G[u]){
            int v = edge[i].other(u);
            if(v ^ p){
                depth[v] = depth[u] + 1;
                d[v] = d[u] + edge[i].w;
                pre_dfs(v, u);
                st[++cnt][0] = u;
            }
        }
    }

    void build(void){
        pre_dfs(1);
        for (int i = 1; MASK(i) <= cnt; ++i){
            for (int u = 1; u + MASK(i) - 1 <= cnt; ++u){
                st[u][i] = MIN_HIGH(st[u][i - 1], st[u + MASK(i - 1)][i - 1]);
            }
        }
    }

    int lca(int u, int v){
        int l = pos[u], r = pos[v];
        if(l > r) swap(l, r);
        int k = 31 - __builtin_clz(r - l + 1);
        return MIN_HIGH(st[l][k], st[r - MASK(k) + 1][k]);
    }


    set<int> mySet;
    int sum = 0;
    int dis(int u, int v){
        return d[u] + d[v] - 2 * d[lca(u, v)];
    }

    void ins(int x){
        x = tin[x];
        if(mySet.empty()){
            mySet.insert(x);
            return;
        }
        if(mySet.size() == 1){
            sum += 2 * dis(rev[*mySet.begin()], rev[x]);
            mySet.insert(x);
            return;
        }
        auto it = mySet.lower_bound(x);
        int l = -1, r = -1;

        if(it == mySet.begin() || it == mySet.end()){
            l = rev[*mySet.begin()];
            r = rev[*prev(mySet.end())];
        }
        else{
            l = rev[*prev(it)];
            r = rev[*it];
        }
        assert(l != -1); assert(r != -1);
        mySet.insert(x);
        sum += dis(l, rev[x]);
        sum += dis(r, rev[x]);
        sum -= dis(l, r);
    }

    void eras(int x){
        x = tin[x];
        mySet.erase(x);
        if(mySet.size() == 0){
            sum = 0;
            return;
        }
        if(mySet.size() == 1){
            sum -= 2 * dis(rev[x], rev[*mySet.begin()]);
            return;
        }

        int l = -1, r = -1;

        auto it = mySet.lower_bound(x);
        if(it == mySet.begin() || it == mySet.end()){
            l = rev[*mySet.begin()];
            r = rev[*prev(mySet.end())];
        }
        else{
            l = rev[*prev(it)];
            r = rev[*it];
        }
        sum += dis(l, r);
        sum -= dis(l, rev[x]);
        sum -= dis(r, rev[x]);
    }
    int ans(void){
        return sum / 2;
    }
}
#define T           DistanceOnTree

void process(void){
    cin >> numNode;
    for (int i = 1; i < numNode; ++i){
        cin >> edge[i].u >> edge[i].v >> edge[i].w;
        ++edge[i].u, ++edge[i].v;
        G[edge[i].u].emplace_back(i);
        G[edge[i].v].emplace_back(i);
    }
    T :: build();


    cin >> numQuery;
    for (int i = 1; i <= numQuery; ++i){
        int node[5];
        REP(j, 5) {
            cin >> node[j];
            ++node[j];
            T :: ins(node[j]);
        }
        cout << T :: ans() << '\n';
        REP(j, 5){
            T :: eras(node[j]);
        }
    }
}
signed main(){
    #define name "Whisper"
    cin.tie(nullptr) -> sync_with_stdio(false);
    //freopen(name".inp", "r", stdin);
    //freopen(name".out", "w", stdout);
    process();
    return (0 ^ 0);
}

• Subtask 1: 7 / 7
• Subtask 2: 23 / 23
• Subtask 3: 40 / 40
• Subtask 4: 30 / 30