Submission #1014640

#	Time	Username	Problem	Language	Result	Execution time	Memory
1014640		vjudge1	Event Hopping 2 (JOI21_event2)	C++17	100 / 100	161 ms	48712 KiB

event2

#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, n) for (int i = 0; i < (n); ++i)
#define REPD(i, n) for (int i = (n) - 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 MAX         200005

int numEvent, numChoose;
struct Info{
    int l, r;
    Info(){}
    Info(int _l, int _r): l(_l), r(_r){}
} A[MAX];
template<class T = vector<int>>
    T compress(T& v){
        sort(v.begin(), v.end());
        v.resize(unique(v.begin(), v.end()) - v.begin());
        return v;
    }

vector<int> comp;
int find(int x){
    return lower_bound(comp.begin(), comp.end(), x) - comp.begin() + 1;
}

int nxt[MAX], up[MAX][22];
void process(void){
    cin >> numEvent >> numChoose;
    for (int i = 1; i <= numEvent; ++i){
        cin >> A[i].l >> A[i].r;
        comp.push_back(A[i].l);
        comp.push_back(A[i].r);
    }
    comp = compress(comp);
    int n = 2 * numEvent;
    for (int i = 1; i <= n; ++i) nxt[i] = n + 1;
    for (int i = 1; i <= numEvent; ++i){
        A[i].l = find(A[i].l);
        A[i].r = find(A[i].r);
        minimize(nxt[A[i].l], A[i].r);
    }
    REP(i, 21) FOR(u, 1, n + 1) up[u][i] = n + 1;
    for (int i = n; i > 0; --i){
        up[i][0] = min(up[i + 1][0], nxt[i]);
    }
    for (int i = 1; i <= 20; ++i){
        for (int u = 1; u <= n; ++u){
            up[u][i] = up[up[u][i - 1]][i - 1];
        }
    }
    auto dp = [&](int l, int r) -> int{
        int ans = 0;
        for (int i = 20; i >= 0; --i){
            if (up[l][i] <= r){
                l = up[l][i];
                ans |= MASK(i);
            }
        }
        return ans;
    };
    int ans = dp(1, n);
    if (ans < numChoose) return void(cout << -1);
    set<pair<int, int>> mySet;
    mySet.insert(make_pair(1, n));
    vector<int> ID;
    for (int i = 1; i <= numEvent; ++i){
        auto it = prev(mySet.lower_bound(make_pair(A[i].l + 1, 0)));
        int l, r; tie(l, r) = *it;
        if (A[i].r <= r){
            int nw_ans = ans - dp(l, r) + dp(l, A[i].l) + dp(A[i].r, r) + 1;
            if (nw_ans >= numChoose){
                ans = nw_ans;
                ID.push_back(i);
                mySet.erase(it);
                mySet.insert(make_pair(l, A[i].l));
                mySet.insert(make_pair(A[i].r, r));
            }
        }
    }
    assert((int)ID.size() >= numChoose);
    for (int i = 0; i < numChoose; ++i){
        cout << ID[i] << "\n";
    }
}
signed main(){
    #define name "Whisper"
    cin.tie(nullptr) -> sync_with_stdio(false);
    //freopen(name".inp", "r", stdin);
    //freopen(name".out", "w", stdout);

    process();
}

• Subtask 1: 7 / 7
• Subtask 2: 1 / 1
• Subtask 3: 31 / 31
• Subtask 4: 61 / 61