Submission #1015348

#	Time	Username	Problem	Language	Result	Execution time	Memory
1015348		overwatch9	Watching (JOI13_watching)	C++17	0 / 100	2 ms	604 KiB

watching

#include <bits/stdc++.h>
using namespace std;
int n;
vector <int> events;
vector <vector <bool>> dp;
vector <vector <int>> ready;
int P, Q;
bool solve(int i, int p, int w, int q) {
    if (q > Q)
        return false;
    if (i >= n)
        return true;
    if (ready[i][p] == w)
        return dp[i][p];
    bool ans = false;
    int it;
    if (p >= 1) {
        it = upper_bound(events.begin(), events.end(), events[i] + w - 1) - events.begin();
        ans = solve(it, p-1, w, q);
    }
    it = upper_bound(events.begin(), events.end(), events[i] + 2*w - 1) - events.begin();
    ans |= solve(it, p, w, q+1);
    ready[i][p] = w;
    dp[i][p] = ans;
    return ans;
}
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    cin >> n >> P >> Q;
    events = vector <int> (n);
    for (int i = 0; i < n; i++)
        cin >> events[i];
    sort(events.begin(), events.end());
    if (P + Q >= n) {
        cout << 1 << '\n';
        return 0;
    }
    ready = vector <vector <int>> (n+1, vector <int> (P+1));
    dp = vector <vector <bool>> (n+1, vector <bool> (P+1));
    int lo = 1, hi = 1e9/2;
    while (lo < hi) {
        int mid = lo + (hi - lo) / 2;
        if (solve(0, P, mid, 0))
            hi = mid;
        else
            lo = mid + 1;
    }
    cout << lo << '\n';
}

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