oj.uz

Submission #321024

# Submission time Handle Problem Language Result Execution time Memory
321024 2020-11-10T16:52:04 Z w4123 Watching (JOI13_watching) C++17
0 / 100
 1000 ms 504 KB 
// watching.cpp : 此文件包含 "main" 函数。程序执行将在此处开始并结束。
//

#include <algorithm>
#include <iostream>
using namespace std;
int arr[2005];
int n, p, q;

int dp[2005][2];
int save[2005][2];
bool saved[2005];
bool check(int mid)
{
	for (int i = 1; i <= n; i++)
	{
		for (int j = 0; j <= 1; j++)
		{
			dp[i][j] = 1000000000;
		}
	}
	fill(saved, saved + n + 1, false);

	for (int c = 0; c <= p; c++)
	{
		for (int i = 1; i <= n; i++)
		{
			int j1;
			int j2;
			if (saved[i])
			{
				j1 = save[i][0];
				j2 = save[i][1];
			}
			else
			{
				j1 = i - 1;
				while (j1 >= 1 && arr[i] - arr[j1] + 1 <= mid) j1--;
				j2 = j1;
				while (j2 >= 1 && arr[i] - arr[j2] + 1 <= 2 * mid)j2--;
				save[i][0] = j1;
				save[i][1] = j2;
				saved[i] = true;
			}

			if (c > 0)dp[i][c&1] = min(dp[i][c&1], dp[j1][(c - 1)&1]);
			dp[i][c&1] = min(dp[i][c&1], dp[j2][c&1] + 1);
		}
	}
	return dp[n][p&1] <= q; 
}

int main()
{
	cin >> n >> p >> q;
	for (int i = 1; i <= n; i++)
	{
		cin >> arr[i];
	}
	sort(arr + 1, arr + n + 1);

	int l = 1, r = 1000000000;
	while(l < r)
	{
		int mid = l + (r - l) / 2;
		if (check(mid))
		{
			r = mid;
		}
		else
		{
			l = mid + 1;
		}
		//cout << l << " " << r << endl;
	}
	cout << r;
}

// 运行程序: Ctrl + F5 或调试 >“开始执行(不调试)”菜单
// 调试程序: F5 或调试 >“开始调试”菜单

// 入门使用技巧: 
//   1. 使用解决方案资源管理器窗口添加/管理文件
//   2. 使用团队资源管理器窗口连接到源代码管理
//   3. 使用输出窗口查看生成输出和其他消息
//   4. 使用错误列表窗口查看错误
//   5. 转到“项目”>“添加新项”以创建新的代码文件，或转到“项目”>“添加现有项”以将现有代码文件添加到项目
//   6. 将来，若要再次打开此项目，请转到“文件”>“打开”>“项目”并选择 .sln 文件

Subtask #1
0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 364 KB Output is correct
2 Correct 0 ms 364 KB Output is correct
3 Correct 0 ms 364 KB Output is correct
4 Execution timed out 1091 ms 364 KB Time limit exceeded
5 Halted 0 ms 0 KB -

Subtask #2
0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 60 ms 364 KB Output is correct
2 Correct 0 ms 364 KB Output is correct
3 Correct 317 ms 504 KB Output is correct
4 Execution timed out 1036 ms 364 KB Time limit exceeded
5 Halted 0 ms 0 KB -