Submission #464322

#	Time	Username	Problem	Language	Result	Execution time	Memory
464322		Hamed5001	Watching (JOI13_watching)	C++14	0 / 100	76 ms	408 KiB

watching

#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

const int mxN = 2e3+10;
ll A[mxN], N, P, Q;

bool ok(ll mid) {
	vector<bool> covered(N, 0);
	
	int PP = P, QQ = Q;
	while(QQ--) {
		bool done = 1;
		int idx = -1, val = 0;
		for (int i = 0; i < N; i++) {
			int cnt = 0;
			if (!covered[i]) {
				int ii = i;
				while(ii < N && A[ii] < A[i] + 2 * mid) {
					cnt+=!covered[ii++];
				}
				if (cnt > val) {
					val = cnt;
					idx = i;
				}
				done = 0;
			}
		}
		if (done) break;
		for (int i = idx; i < idx + val; i++)
			covered[i] = 1;
	}


	for (int i = 0; i < N; i++) {
		if (!covered[i]) {
			PP--;
			int ii = i;
			while(ii < N && A[ii] < A[i] + mid)
				covered[ii++] = 1;
		}
	}
	return PP >= 0;
}

void solve() {
	cin >> N >> P >> Q;
	set<int> st;
	for (int i = 0; i < N; i++) {
		int x;
		cin >> x;
		st.insert(x);
	}

	int i = 0;
	for (auto it : st) {
		A[i++] = it;
	}
	N = st.size();

	ll l = 1, r = 1e10, mid;
	while(l < r) {
		mid = (l+r) >> 1;
		if (ok(mid)) r = mid;
		else l = mid+1;
	}
	cout << r << endl;
}

int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	solve();
}

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