Submission #1031730

#	Time	Username	Problem	Language	Result	Execution time	Memory
1031730		juicy	구경하기 (JOI13_watching)	C++17	100 / 100	40 ms	16216 KiB

watching

#include <bits/stdc++.h>

using namespace std;

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

int main() {
	ios::sync_with_stdio(false); cin.tie(nullptr);

	int N, P, Q; cin >> N >> P >> Q; 
	P = min(P, N);
	Q = min(Q, N);
	vector<int> A(N);
	for (int i = 0; i < N; ++i) {
		cin >> A[i];
	}
	sort(A.begin(), A.end());
	vector dp(P + 1, vector<int>(Q + 1));
	vector<array<int, 2>> nxt(N);
	auto check = [&](int md) {
		nxt[N - 1][0] = nxt[N - 1][1] = N - 1;
		for (int i = N - 2; ~i; --i) {
			for (int j = 1; j <= 2; ++j) {
				int &p = nxt[i][j - 1];
				p = nxt[i + 1][j - 1];
				while (A[p] - A[i] >= j * md) {
					--p;
				}
			} 
		}
		for (int i = 0; i <= P; ++i) {
			fill(dp[i].begin(), dp[i].end(), -1);
		}
		dp[0][0] = 0;
		for (int i = 0; i <= P; ++i) {
			for (int j = 0; j <= Q; ++j) {
				if (dp[i][j] != -1) {
					if (dp[i][j] == N) {
						return true;
					}
					if (i + 1 <= P) {
						dp[i + 1][j] = max(dp[i + 1][j], nxt[dp[i][j]][0] + 1);
					}
					if (j + 1 <= Q) {
						dp[i][j + 1] = max(dp[i][j + 1], nxt[dp[i][j]][1] + 1);
					}
				}
			}
		}
		return false;
	};	
	int l = 1, r = 1e9, res = 1e9;
	while (l <= r) {
		int md = (l + r) / 2;
		if (check(md)) {
			res = md;
			r = md - 1;
		} else {
			l = md + 1;
		}
	}
	cout << res;
	return 0;
}

• Subtask 1: 50 / 50
• Subtask 2: 50 / 50