Submission #1000100

#	Time	Username	Problem	Language	Result	Execution time	Memory
1000100		vjudge1	Sparklers (JOI17_sparklers)	C++17	0 / 100	0 ms	348 KiB

sparklers

#include <bits/stdc++.h>

using namespace std;

#define int long long
#define inf 0x3F3F3F3F3F3F3F3F

const int MXN = 1e5 + 5;

signed main()
{
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	int n, k, t;
	cin >> n >> k >> t;
	k--;
	int x[n];
	for (int &i : x) cin >> i;
	int l = 0, r = inf;
	while (l < r)
	{
		int mid = (l + r) >> 1;
		int L = k - 1, R = k + 1;
		int cnt = 1;
		while (1)
		{
			if (L >= 0 && (R >= n || x[k] - x[L] <= x[R] - x[k]))
			{
				if ((x[R - 1] - x[L] + mid * 2 - 1) / (mid * 2) > cnt * t) break;
				L--;
				cnt++;
			}
			else if (R < n && (L < 0 || x[k] - x[L] >= x[R] - x[k]))
			{
				if ((x[R] - x[L + 1] + mid * 2 - 1) / (mid * 2) > cnt * t) break;
				R++;
				cnt++;
			}
			else break;
		}
		if (cnt == n) r = mid;
		else l = mid + 1;
	}
	cout << l << '\n';
}

• Subtask 1: 0 / 30
• Subtask 2: 0 / 20
• Subtask 3: 0 / 50