Submission #794536

#	Time	Username	Problem	Language	Result	Execution time	Memory
794536		ono_de206	Abracadabra (CEOI22_abracadabra)	C++14	50 / 100	3067 ms	48400 KiB

Main

#include<bits/stdc++.h>
using namespace std;

#define fast ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define in insert
#define all(x) x.begin(),x.end()
#define pb push_back
#define eb emplace_back
#define ff first
#define ss second

// #define int long long
 
typedef long long ll;
typedef vector<int> vi;
typedef set<int> si;
typedef multiset<int> msi;
typedef pair<int, int> pii;
typedef vector<pii> vpii;

template<typename T, typename U>
ostream & operator << (ostream &out, const pair<T, U> &c) {
	out << c.first << ' ' << c.second;
    return out;
}

template<typename T>
ostream & operator << (ostream &out, vector<T> &v) {
	const int sz = v.size();
	for (int i = 0; i < sz; i++) {
		if (i) out << ' ';
		out << v[i];
	}
    return out;
}

template<typename T>
istream & operator >> (istream &in, vector<T> &v) {
	for (T &x : v) in >> x;
    return in;
}


template<typename T>
void mxx(T &a, T b){if(b > a) a = b;}
template<typename T>
void mnn(T &a, T b){if(b < a) a = b;}

const int mxn = 2e5 + 10, mxq = 1e6 + 10;
vector<pair<int, int>> qu[mxn];
int a[mxn], ans[mxq], nxt[mxn], did[mxn];

signed main() {
	fast;
	int n, q;
	cin >> n >> q;
	for(int i = 1; i <= n; i++) {
		cin >> a[i];
		did[i] = -1;
	}

	for(int i = 1; i <= q; i++) {
		int t, id;
		cin >> t >> id;
		mnn(t, n);
		if(t == 0) {
			ans[i] = a[id];
		} else {
			qu[t].eb(id, i);
		}
	}

	stack<pair<int, int>> st;
	for(int i = 1; i <= n; i++) {
		nxt[i] = n + 1;
	}
	nxt[n + 1] = n + 1;
	for(int i = 1; i <= n; i++) {
		while(st.size() && st.top().ff < a[i]) {
			nxt[st.top().ss] = i;
			st.pop();
		}
		st.emplace(a[i], i);
	}

	set<pair<int, pair<int, int>>> s;
	for(int i = 1; i <= n; i = nxt[i]) {
		s.emplace(a[i], make_pair(i, nxt[i] - 1));
		assert(i <= nxt[i] - 1);
	}

	int len = n;

	for(int t = 1; t <= n; t++) {
		while(1) {
			auto val = *s.rbegin();
			if(len - (val.ss.ss - val.ss.ff + 1) >= n / 2) {
				len -= (val.ss.ss - val.ss.ff + 1);
				for(int i = val.ss.ff; i <= val.ss.ss; i++) {
					did[len + (i - val.ss.ff + 1)] = a[i];
				}
				s.erase(*s.rbegin());
			} else {
				break;
			}
		}
		if(len > n / 2) {
			auto val = *s.rbegin();
			s.erase(*s.rbegin());
			len -= (val.ss.ss - val.ss.ff + 1);
			s.emplace(val.ff, make_pair(val.ss.ff, val.ss.ff + n / 2 - len - 1));
			for(int i = val.ss.ff + n / 2 - len; i <= val.ss.ss; i = nxt[i]) {
				s.emplace(a[i], make_pair(i, min(nxt[i] - 1, val.ss.ss)));
			}
			len += (val.ss.ss - val.ss.ff + 1);
		}
		sort(all(qu[t]));
		auto it = s.begin();
		int lol = 0;
		for(auto U : qu[t]) {
			int id = U.ff;
			int i = U.ss;
			if(id > len) {
				ans[i] = did[id];
				continue;
			}
			while(it != s.end() && lol + (*it).ss.ss - (*it).ss.ff + 1 < id) {
				lol += (*it).ss.ss - (*it).ss.ff + 1;
				it++;
			}
			ans[i] = a[(*it).ss.ff + id - lol - 1];
		}
	}
	
	for(int i = 1; i <= q; i++) {
		cout << ans[i] << '\n';
	}
	return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 40 / 40
• Subtask 3: 0 / 25
• Subtask 4: 0 / 25