oj.uz

Submission #824157

# Submission time Handle Problem Language Result Execution time Memory
824157 2023-08-13T16:03:15 Z Koyote Watching (JOI13_watching) C++14
100 / 100
 179 ms 16020 KB 
#include <bits/stdc++.h>
using namespace std;

const int N = 2e3 + 2;
int n, p, q, a[N];
int dp[N][N]; // dp[i][j]: number of small cameras needed to take pictures of i events with j big cameras

int main() {
    cin.tie(nullptr)->sync_with_stdio(false);
    cin >> n >> p >> q;
    for (int i = 1; i <= n; i++) cin >> a[i];
    sort(a + 1, a + n + 1);

    if (p + q >= n) return cout << 1 << '\n', 0;

    auto binary_func = [&](int x) {
        memset(dp, 0x7f, sizeof(dp));
        dp[0][0] = 0;
        for (int i = 1; i <= n; i++) {
            int sl = 1, bl = 1;
            while (a[i] - a[sl] + 1 > x) sl++;
            while (a[i] - a[bl] + 1 > 2 * x) bl++;
            for (int j = 0; j <= q; j++) {
                dp[i][j] = dp[sl - 1][j] + 1;
                if (j > 0) dp[i][j] = min(dp[i][j], dp[bl - 1][j - 1]);
            }
        }
        for (int j = 0; j <= q; j++) if (dp[n][j] <= p) return true;
        return false;
    };

    int lo = 1, hi = int(1e9);
    while (lo <= hi) {
        int mid = (lo + hi) >> 1;
        if (binary_func(mid)) hi = mid - 1;
        else lo = mid + 1;
    }
    cout << lo << '\n';
}

Subtask #1
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 24 ms 15956 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 33 ms 15988 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 26 ms 15956 KB Output is correct
8 Correct 25 ms 15940 KB Output is correct
9 Correct 25 ms 16008 KB Output is correct
10 Correct 25 ms 15956 KB Output is correct
11 Correct 27 ms 16008 KB Output is correct
12 Correct 27 ms 16012 KB Output is correct
13 Correct 26 ms 15988 KB Output is correct
14 Correct 28 ms 15992 KB Output is correct
15 Correct 27 ms 16012 KB Output is correct

Subtask #2
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 47 ms 15956 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 1 ms 336 KB Output is correct
4 Correct 1 ms 352 KB Output is correct
5 Correct 1 ms 340 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 84 ms 16020 KB Output is correct
8 Correct 109 ms 16016 KB Output is correct
9 Correct 81 ms 16016 KB Output is correct
10 Correct 84 ms 16012 KB Output is correct
11 Correct 179 ms 16020 KB Output is correct
12 Correct 119 ms 16020 KB Output is correct
13 Correct 66 ms 16016 KB Output is correct
14 Correct 84 ms 16016 KB Output is correct
15 Correct 80 ms 16016 KB Output is correct