Submission #1265795

#	Time	Username	Problem	Language	Result	Execution time	Memory
1265795		canhnam357	Watching (JOI13_watching)	C++20	100 / 100	242 ms	16112 KiB

watching

#include <bits/stdc++.h>
using namespace std;
#define N 2001
int dp[N][N];
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int n, p, q;
    cin >> n >> p >> q;
    vector<int> a(n);
    for (int &i : a) cin >> i;
    sort(a.begin(), a.end());
    p = min(p, n);
    q = min(q, n);
    auto can = [&](int m) {
        for (int i = 0; i < n; i++) {
            for (int j = 0; j <= p; j++) {
                dp[i][j] = q + 1;
            }
        }
        for (int l = 0, r = 0, k = 0; r < n; r++) {
            while (a[r] - a[l] + 1 > m) l++;
            while (a[r] - a[k] + 1 > 2 * m) k++;
            if (l == 0) {
                dp[r][0] = 1;
                dp[r][1] = 0;
            }
            else {
                if (k == 0) {
                    dp[r][0] = 1;
                    for (int i = 1; i <= p; i++) {
                        dp[r][i] = min(dp[r][i], dp[l - 1][i - 1]);
                    }
                }
                else {
                    for (int i = 1; i <= p; i++) {
                        dp[r][i] = min(dp[r][i], dp[l - 1][i - 1]);
                    }
                    for (int i = 0; i <= p; i++) {
                        if (dp[k - 1][i] < q) dp[r][i] = min(dp[r][i], dp[k - 1][i] + 1);
                    }
                }
            }
        }
        return *min_element(dp[n - 1], dp[n - 1] + p + 1) <= q;
    };
    int l = 0, r = 1e9 + 1;
    while (r - l > 1) {
        int m = (l + r) >> 1;
        if (can(m)) r = m;
        else l = m;
    }
    cout << r;
    return 0;
}

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