제출 #1281041

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1281041		ksjsjsjsjsjsjs	Feast (NOI19_feast)	C++20	100 / 100	178 ms	21568 KiB

feast

#include <bits/stdc++.h>
using namespace std;
mt19937 rd(chrono::steady_clock::now().time_since_epoch().count());
long long rand(long long l, long long r) {
	return uniform_int_distribution<long long>(l, r)(rd);
}
#define int long long
#define pussy pair<__int128, int>
const int oo = 3e14 + 5;
const int N = 3e5 + 5;
int n, k, a[N];
pussy d[N][2];
pussy dp(int lambda) {
	for (int i = 1; i <= n; ++i) {
		for (int j = 0; j < 2; ++j) {
			// dont take
			d[i][j] = d[i - 1][0];
			// take new segment
			d[i][j] = max(d[i][j], {d[i - 1][1].first + a[i] - lambda, d[i - 1][1].second + 1});
			// continue current segment
			if (j) d[i][j] = max(d[i][j], {d[i - 1][1].first + a[i], d[i - 1][1].second});
		}
	}
	return d[n][0];
}
signed main() {
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	#ifdef LOCAL
		// freopen("TEST.inp", "r", stdin);
		// freopen("TEST.out", "w", stdout);
	#else
		// freopen("TEST.inp", "r", stdin);
		// freopen("TEST.out", "w", stdout);
	#endif
	cin >> n >> k;
	for (int i = 1; i <= n; ++i) {
		cin >> a[i];
	}
	int l = -oo, r = oo, cut = -oo;
	while (l <= r) {
		int mid = l + (r - l) / 2;
		auto [sum, cnt] = dp(mid);
		if (cnt >= k) {
			cut = mid;
			l = mid + 1;
		}
		else r = mid - 1;
	}
	// cerr << "DB>> " << cut << '\n';
	int ans = 0;
	if (cut >= 0) {
		auto [sum, cnt] = dp(cut);
		ans = sum + k * cut;
	}
	else {
		auto [sum, cnt] = dp(0);
		ans = sum;
	}
	cout << ans << '\n';
	return 0;
}

• Subtask 1: 4 / 4
• Subtask 2: 8 / 8
• Subtask 3: 18 / 18
• Subtask 4: 10 / 10
• Subtask 5: 11 / 11
• Subtask 6: 20 / 20
• Subtask 7: 29 / 29