제출 #705477

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
705477		pavement	Bigger segments (IZhO19_segments)	C++17	13 / 100	1 ms	340 KiB

segments

#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;
//~ #define int long long
#define mp make_pair
#define mt make_tuple
#define pb push_back
#define ppb pop_back
#define eb emplace_back
#define g0(a) get<0>(a)
#define g1(a) get<1>(a)
#define g2(a) get<2>(a)
#define g3(a) get<3>(a)
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
using db = double;
using ll = long long;
using ld = long double;
using ii = pair<int, int>;
using iii = tuple<int, int, int>;
using iiii = tuple<int, int, int, int>;
template<class key, class value = null_type, class cmp = less<key> >
using ordered_set = tree<key, value, cmp, rb_tree_tag, tree_order_statistics_node_update>;

int n, a[500005];
ll p[500005];
pair<int, ll> dp[500005];
set<pair<int, pair<int, ll> > > S;

pair<int, ll> qry(ll p) {
	auto it = S.upper_bound(mp(p, mp(INT_MAX, LLONG_MAX)));
	if (it == S.begin()) return mp(-1, -1ll);
	--it;
	return it->second;
}

void upd(ll p, pair<int, ll> v) {
	if (qry(p) >= v) return;
	auto it = S.lower_bound(mp(p, mp(-1, -1ll)));
	vector<set<pair<int, pair<int, ll> > >::iterator> to_del;
	while (it != S.end() && it->second <= v) {
		to_del.pb(it);
		++it;
	}
	for (auto it : to_del) S.erase(it);
	S.emplace(p, v);
}

main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> a[i];
		p[i] = a[i] + p[i - 1];
		assert(-(ll)1e16 <= p[i] && p[i] <= (ll)1e16);
		auto tmp = qry(p[i]);
		tmp.second -= p[i];
		dp[i] = max(mp(1, -p[i]), tmp);
		assert(-(ll)1e16 <= p[i] - dp[i].second && p[i] - dp[i].second <= (ll)1e16);
		upd(p[i] - dp[i].second, mp(dp[i].first + 1, p[i]));
	}
	cout << dp[n].first << '\n';
}

컴파일 시 표준 에러 (stderr) 메시지

segments.cpp:50:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   50 | main() {
      | ^~~~

• Subtask 1: 13 / 13
• Subtask 2: 0 / 14
• Subtask 3: 0 / 10
• Subtask 4: 0 / 36
• Subtask 5: 0 / 27