Submission #1306539

#	Time	Username	Problem	Language	Result	Execution time	Memory
1306539		Tymond	Event Hopping 2 (JOI21_event2)	C++20	100 / 100	102 ms	15412 KiB

event2

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
#define fi first
#define se second
#define vi vector<int>
#define vll vector<long long>
#define pii pair<int, int>
#define pll pair<long long, long long>
#define pb push_back
#define mp make_pair
#define eb emplace_back
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
mt19937_64 rng64(chrono::high_resolution_clock::now().time_since_epoch().count());
inline int rand(int l,int r){return uniform_int_distribution<int>(l, r)(rng);}
inline ll rand(ll l,ll r){return uniform_int_distribution<ll>(l, r)(rng64);}
#ifdef DEBUG
auto&operator<<(auto&o,pair<auto,auto>p){return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator<<(auto&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<","+!i++<<e;return o<<"}";}
#define debug(X...)cerr<<"["#X"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(X)
#else
#define debug(...){}
#endif

struct custom_hash {
    static uint64_t splitmix64(uint64_t x) {
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }

    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};

struct pair_hash{
  size_t operator()(const pair<int,int>&x)const{
    return hash<long long>()(((long long)x.first)^(((long long)x.second)<<32));
  }
};

const int MAXN = 1e5 + 7;
const int MAXK = 18;
const int INF = 1e9 + 7;
pii A[MAXN];
int jump[MAXN][MAXK];
int n, k;

void preproceesing(){
    vector<pair<pii, int>> vec;
    for(int i = 1; i <= n; i++){
        vec.pb(mp(A[i], i));
    }

    sort(all(vec));

    int best = -1;
    set<pii> s;
    for(auto [range, ind] : vec){
        while(sz(s) && (*s.begin()).fi <= range.fi){
            pii now = *s.begin();
            s.erase(s.begin());
            if(best == -1 || A[best].fi < A[now.se].fi){
                best = now.se;
            }
        }
        jump[ind][0] = best;
        s.insert(mp(range.se, ind));
    }



    for(int j = 1; j < MAXK; j++){
        for(int i = 1; i <= n; i++){
            if(jump[i][j - 1] == -1){
                jump[i][j] = -1;
            }else{
                jump[i][j] = jump[jump[i][j - 1]][j - 1];
            }
        }
    }
    // for(int i = 1; i <= n; i++){
    //     cerr << A[i] << ' ' << jump[i][0] << ' ' << jump[i][1] << ' ' << jump[i][2] << '\n'; 
    // }
}

int calc(int x, int y){
    int res = 0;
    for(int j = MAXK - 1; j >= 0; j--){
        //cerr << x << ' ' << res << ' ' << j << ' ' << jump[x][j] << '\n';
        if(jump[x][j] == -1 || A[jump[x][j]].fi < A[y].se || jump[x][j] == y){
            continue;
        }
        if(A[jump[x][j]].fi >= A[y].se){
            res += (1 << j);
            x = jump[x][j];
        }
    }
    return res;
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);

    cin >> n >> k;
    for(int i = 3; i <= n + 2; i++){
        cin >> A[i].fi >> A[i].se;
    }

    A[1] = mp(0, 0);
    A[2] = mp(INF, INF);
    n += 2;

    preproceesing();

    set<pair<pii, int>> intervals;
    intervals.insert(mp(A[1], 1));
    intervals.insert(mp(A[2], 2));
    vi P = {};
    int len = 2 + calc(2, 1);
    k += 2;
    if(len < k){
        cout << "-1\n";
        return 0;
    }
    //cerr << len << ' ' << k << '\n';
    for(int i = 3; i <= n; i++){
        if(sz(P) == k - 2){
            break;
        }

        auto it = intervals.lower_bound(mp(A[i], 0));
        if((*it).fi.fi < A[i].se){
            continue;
        }

        auto pre = it;
        pre--;
        if((*pre).fi.se > A[i].fi){
            continue;
        }

        int preLen = len;
        len -= calc((*it).se, (*pre).se);
        len += (1 + calc(i, (*pre).se) + calc((*it).se, i));
        if(len >= k){
            P.pb(i);
            intervals.insert(mp(A[i], i));
        }else{
            len = preLen;
        }
    }

    for(auto ele : P){
        cout << ele - 2 << '\n';
    }

    return 0;
}

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