Submission #553296

#	Time	Username	Problem	Language	Result	Execution time	Memory
553296		RaresFelix	Collapse (JOI18_collapse)	C++17	100 / 100	5305 ms	459620 KiB

collapse

#include "collapse.h"
#include <bits/stdc++.h>
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")

using namespace std;
using Edge = tuple<int, int, int, int>; //from, to, begin, end
using vEd = vector<Edge>;
using vi = vector<int>;


struct RollbackUF {
    vi e; vector<pair<int, int> > st;
    RollbackUF(int n) : e(n, -1) {}
    int size(int x) { return -e[find(x)]; }
    int find(int x) { return e[x] < 0 ? x : find(e[x]); }
    int time() { return int(st.size()); }
    void rollback(int t) {
        for (int i = time(); i --> t;)
            e[st[i].first] = st[i].second;
        st.resize(t);
    }
    bool join(int a, int b) {
        a = find(a), b = find(b);
        if (a == b) return false;
        if (e[a] > e[b]) swap(a, b);
        st.push_back({a, e[a]});
        st.push_back({b, e[b]});
        e[a] += e[b]; e[b] = a;
        return true;
    }
};

struct Bucket {
    RollbackUF Simu;
    int begin, end;
    Bucket(int n, int begin, int end) : Simu(n), begin(begin), end(end) {}
    vector<Edge> idk;
    void add_edge(Edge nou) {
        auto &[f, t, b, e] = nou;
        if(e < begin || end < b) return;
        if(b <= begin && end <= e) { //complet
            Simu.join(f, t);
            return;
        }
        idk.push_back(nou);
    }
    int query(int timp) {
        int count0 = Simu.time();
        for(auto &it : idk) {
            auto &[f, t, b, e] = it;
            if(b <= timp && timp <= e) Simu.join(f, t);
        }
        int re = Simu.st.size() >> 1;
        Simu.rollback(count0);
        return re;
    }
};

void solve(int n, int c, int q, vEd &edges, vi &W, vi &P, vi &R) {
    R.assign(q, 0);
    vector<vi> Queries(n + 2);
    for(int i = 0; i < q; ++i)
        Queries[P[i]].push_back(i);
    vector<vEd> Add(n + 1);
    for(auto &[f, t, b, e] : edges)
        Add[t].push_back({f, t, b, e});

    int bucketSize = int(sqrt(c + 1));
    vector<Bucket> Sol;
    for(int lp = 0; lp <= c + 1; lp += bucketSize)
        Sol.emplace_back(n, lp, lp + bucketSize - 1);

    for(int i = 0; i < n; ++i) {
        for(auto &it : Add[i])
            for(auto &seg : Sol) seg.add_edge(it);
        for(auto &qid : Queries[i]) {
            int w = W[qid];
            int re = 0;
            for(auto &seg : Sol) {
                if(seg.begin <= w && w <= seg.end) {
                    re = seg.query(w);
                    break;
                }
            }
            R[qid] = i + 1 - re;
        }
    }
}

vector<int> simulateCollapse(
        int n,
        vector<int> T,
        vector<int> X,
        vector<int> Y,
        vector<int> W,
        vector<int> P
) {
    vEd edges;
    int c = T.size(), q = W.size();
    map<pair<int, int>, int> enabled;
    for(int i = 0 ; i < c; ++i)
        if(X[i] > Y[i]) swap(X[i], Y[i]);
    for(int i = 0 ; i < c; ++i) {
        if(!T[i])
            enabled[{X[i], Y[i]}] = i;
        else {
            edges.push_back({X[i], Y[i], enabled[{X[i], Y[i]}], i - 1});
            enabled[{X[i], Y[i]}] = -1;
        }
    }
    for(auto [p, e] : enabled) if(e != -1) {
            auto [f, t] = p;
            edges.push_back({f, t, e, c + 1});
        }
    vector<int> R, R1, R2;
    solve(n, c, q, edges, W, P, R1);
    for(auto &it : P) it = n - 2 - it;
    for(auto &[a, b, c, d] : edges)
        a = n - 1 - a, b = n - 1 - b, a ^= b, b ^= a, a ^= b;
    solve(n, c, q, edges, W, P, R2);
    for(int i = 0; i < q; ++i) R.push_back(R1[i] + R2[i]);
    return R;
}

• Subtask 1: 5 / 5
• Subtask 2: 30 / 30
• Subtask 3: 30 / 30
• Subtask 4: 35 / 35