Submission #651600

#	Time	Username	Problem	Language	Result	Execution time	Memory
651600		Koful123	Watching (JOI13_watching)	C++17	50 / 100	1081 ms	74960 KiB

watching

#include <bits/stdc++.h>
using namespace std;
#define endl "\n"
#define pb push_back
#define ff first
#define ss second
#define mod 1000000007
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()

int n,p,q;
const int N = 2e3 + 5;
long long v[N];
vector<vector<vector<bool>>> dp,ok;

int get(long long val){
	int l = 0,r = n-1;
	while(l < r){
		int m = (l + r) / 2;
		if(val <= v[m]) r = m;
		else l = m + 1;
	}
	return l + (v[n-1] < val);
}

bool f(int pos,int p,int q,long long w){
	if(p < 0 || q < 0) return false;
	if(pos == n) return true;
	if(ok[pos][p][q]) return dp[pos][p][q];
	int a = get(v[pos] + w);
	int b = get(v[pos] + 2*w);
	dp[pos][p][q] = (f(a,p-1,q,w) || f(b,p,q-1,w)); ok[pos][p][q] = true;
	return dp[pos][p][q];
}

bool check(long long m){
	dp.assign(n,vector<vector<bool>>(p+1,vector<bool>(q+1,false)));
	ok.assign(n,vector<vector<bool>>(p+1,vector<bool>(q+1,false)));
	return f(0,p,q,m);
}

void solve(){

	cin >> n >> p >> q;
	for(int i=0;i<n;i++){
		cin >> v[i];
	}

	if(p + q >= n){
		cout << 1 << endl;
		return;
	}

	sort(v,v+n);
	int l = 1,r = 1e9;
	while(l < r){
		int m = (l + r) / 2;
		if(check(m)) r = m;
		else l = m + 1;
	}

	cout << l << endl;
}	

signed main(){

	ios::sync_with_stdio(0);
	cin.tie(0);

	int t = 1;
//	cin >> t;

	while(t--)
		solve();

	return 0;
}

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