Submission #1168014

#	Time	Username	Problem	Language	Result	Execution time	Memory
1168014		tsengang	Watching (JOI13_watching)	C++20	0 / 100	15 ms	324 KiB

watching

#include <bits/stdc++.h>
#define ll long long
#define ff first
#define ss second
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define pb push_back
#define ertunt return
#define vodka void
using namespace std;
int main() {
    ll n, p, q;
    cin >> n >> p >> q;
    if (p + q >= n) {
        cout << 1;
        ertunt 0;
    }
    ll a[n];
    for (ll i = 0; i < n; i++) cin >> a[i];
    ll l = 1, r = 1e9 + 5;
    while (l < r) {
        ll m = (l + r) / 2;
        ll dp[n + 4][p + 1][q + 1] = {};
        for (ll i = n - 1; i >= 0; i--) {
            for (ll j = p; j >= 0; j--) {
                for (ll k = q; k >= 0; k--) {
                    if (k > 0) {
                        ll cur = i;
                        while (cur < n - 1 and a[cur + 1] < a[i] + 2 * m) cur++;
                        if (cur == n - 1) {
                            dp[i][j][k] = 1;
                            continue;
                        }
                        dp[i][j][k] = max(dp[cur + 1][j][k - 1], dp[i][j][k]);
                    }
                    if (j > 0) {
                        ll cur = i;
                        while (cur < n - 1 and a[cur + 1] < a[i] + m) cur++;
                        if (cur == n - 1) {
                            dp[i][j][k] = 1;
                            continue;
                        }
                        dp[i][j][k] = max(dp[cur + 1][j - 1][k], dp[i][j][k]);
                    }
                }
            }
        }
        if (dp[0][p][q] == 1) r = m;
        else l = m + 1;
    }
    cout << l;
}

• Subtask 1: 0 / 50
• Subtask 2: 0 / 50