oj.uz

Submission #256830

# Submission time Handle Problem Language Result Execution time Memory
256830 2020-08-03T09:09:10 Z islingr Watching (JOI13_watching) C++17
100 / 100
 178 ms 16536 KB 
#include <bits/stdc++.h>
using namespace std;

const int N = 1 << 11;
int n, P, Q, a[N], dp[N][N];

bool f(int w) {
	for (int i = 1; i <= n; ++i) {
		int j = i, k = i;
		while (j && a[i] - a[j] < w) --j;
		while (k && a[i] - a[k] < 2 * w) --k;
		dp[i][0] = 1 + dp[k][0];
		for (int p = 1; p <= P; ++p) dp[i][p] = min(dp[j][p - 1], 1 + dp[k][p]);
	}
	return dp[n][P] <= Q;
}

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

	cin >> n >> P >> Q;
	for (int i = 1; i <= n; ++i) cin >> a[i];
	if (n <= P) return cout << 1, 0;
	sort(a + 1, a + n + 1);
	int l = 0, r = a[n] - a[1] + 1;
	while (r - l > 1) {
		int m = l + (r - l + 1) / 2;
		(f(m) ? r : l) = m;
	}
	cout << r;
}

Subtask #1
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 768 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 0 ms 384 KB Output is correct
4 Correct 0 ms 384 KB Output is correct
5 Correct 1 ms 768 KB Output is correct
6 Correct 0 ms 384 KB Output is correct
7 Correct 1 ms 768 KB Output is correct
8 Correct 1 ms 768 KB Output is correct
9 Correct 1 ms 768 KB Output is correct
10 Correct 1 ms 768 KB Output is correct
11 Correct 1 ms 768 KB Output is correct
12 Correct 1 ms 768 KB Output is correct
13 Correct 1 ms 768 KB Output is correct
14 Correct 1 ms 768 KB Output is correct
15 Correct 1 ms 768 KB Output is correct

Subtask #2
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 77 ms 8448 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 166 ms 16384 KB Output is correct
4 Correct 1 ms 384 KB Output is correct
5 Correct 36 ms 8448 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 30 ms 8448 KB Output is correct
8 Correct 30 ms 8448 KB Output is correct
9 Correct 100 ms 16536 KB Output is correct
10 Correct 178 ms 16376 KB Output is correct
11 Correct 29 ms 8448 KB Output is correct
12 Correct 105 ms 16384 KB Output is correct
13 Correct 17 ms 8448 KB Output is correct
14 Correct 19 ms 8448 KB Output is correct
15 Correct 20 ms 8448 KB Output is correct