Submission #1139966

#	Time	Username	Problem	Language	Result	Execution time	Memory
1139966		jackofall718	Watching (JOI13_watching)	C++20	0 / 100	0 ms	648 KiB

watching

#include <bits/stdc++.h>
#include <chrono>
#define ll long long int
#define endl '\n'
#define vn vector<ll>
#define vi vector<pair <ll,ll>>

using namespace std;
using namespace std::chrono;
const int MAX_N = 1e9 + 7;
#define pii pair<ll,ll>
const ll INF = 0x3f3f3f3f3f3f3f3f;

#define pb push_back  
#define srt(vp) sort(vp.begin(), vp.end()) 

bool canCover(ll w, const vn &v, int p, int q) {
    int n = v.size();
    p = min(p, n);
    q = min(q, n);
    vector<vector<int>> dp(p+1, vector<int>(q+1, -1));
    dp[0][0] = 0;

    for (int i = 0; i <= p; i++) {
        for (int j = 0; j <= q; j++) {
            if (dp[i][j] == -1) continue;
            int curr = dp[i][j];
            if (curr >= n) return true;

            if (i < p) {
                int k = upper_bound(v.begin(), v.end(), v[curr] + w) - v.begin() - 1;
                dp[i+1][j] = max(dp[i+1][j], k + 1);
            }
            if (j < q) {
                int k = upper_bound(v.begin(), v.end(), v[curr] + 2 * w) - v.begin() - 1;
                dp[i][j+1] = max(dp[i][j+1], k + 1);
            }
        }
    }
    return dp[p][q] >= n;
}

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

    ll n, p, q;
    cin >> n >> p >> q;
    vn v(n);
    for (ll &x : v) cin >> x;
    sort(v.begin(), v.end());

    ll lo = 1, ho = v[n-1] - v[0];
    while (lo <= ho) {
        ll mid = (lo + ho) / 2;
        if (canCover(mid, v, p, q)) {
            ho = mid - 1;
        } else {
            lo = mid + 1;
        }
    }
    cout << lo << endl;

    return 0;
}

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