Submission #1040923

#	Time	Username	Problem	Language	Result	Execution time	Memory
1040923		GrindMachine	Event Hopping 2 (JOI21_event2)	C++17	32 / 100	3044 ms	5776 KiB

event2

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) (int)a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x,y) ((x+y-1)/(y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a,b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a,b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#endif

/*

read the solution a long time ago, remember some key ideas from there

*/

const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

void solve(int test_case)
{
    ll n,k; cin >> n >> k;
    vector<pll> a(n+5);
    rep1(i,n) cin >> a[i].ff >> a[i].ss;
    rep1(i,n) a[i].ss--;

    set<pll> st;
    st.insert({-inf1,-inf1});

    auto ok = [&](ll l, ll r){
        auto it1 = st.lower_bound({l+1,-1});
        it1--;
        auto it2 = st.lower_bound({r+1,-1});
        it2--;
        if(it1 != it2) return false;
        auto [lx,rx] = *it1;
        if((lx <= l and l <= rx) or (lx <= r and r <= rx)) return false;
        return true;        
    };

    vector<ll> ans;

    rep1(i,n){
        if(sz(ans) == k) break;

        auto [l,r] = a[i];
        if(!ok(l,r)) conts;
        st.insert({l,r});

        vector<pll> segs;

        for(int j = i+1; j <= n; ++j){
            auto [lx,rx] = a[j];
            if(!ok(lx,rx)) conts;
            segs.pb({rx,lx});
        }

        sort(all(segs));

        ll prevr = -inf2;
        ll cnt = sz(st)-1;

        for(auto [rx,lx] : segs){
            if(lx > prevr){
                cnt++;
                prevr = rx;
            }
        }

        if(cnt >= k){
            ans.pb(i);
        }
        else{
            st.erase({l,r});
        }
    }

    if(ans.empty()){
        cout << -1 << endl;
    }
    else{
        trav(x,ans) cout << x << endl;
    }
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;

    rep1(i, t) {
        solve(i);
    }

    return 0;
}

• Subtask 1: 0 / 7
• Subtask 2: 1 / 1
• Subtask 3: 31 / 31
• Subtask 4: 0 / 61