Submission #758835

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
758835	2023-06-15T11:11:49 Z	Fidan	Watching (JOI13_watching)	C++17	50 / 100	1000 ms	31768 KB

watching

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rep(i, a, b) for(ll i=ll(a); i<ll(b); i++)
#define repn(i, a, b) for(ll i=ll(b)-1; i>=ll(a); i--)
#define pb push_back
#define si size()
#define ff first
#define ss second
#define be begin()
#define en end()
const ll N=2002, P=2002;
vector<vector<ll>> dp(N, vector<ll> (P, N));
bool check(ll n, ll p, ll q, ll w, vector<ll> &v){
	dp[0][0]=1;
	rep(i, 1, p+1){
		dp[0][i]=0;
	}
	ll c=0;
	rep(i, 1, n){
		if(v[c]+2*w-1>=v[i]){
			dp[i][0]=dp[i-1][0];
		}
		else{
			c=i;
			dp[i][0]=dp[i-1][0]+1;
		}
	}
	rep(i, 1, n){
		rep(j, 1, p+1){
			dp[i][j]=N;
			if(v[0]+w>v[i]){
				dp[i][j]=0;
			}
			else{
				ll lo=0, hi=i-1;
				while(lo<hi){
					ll mid=(lo+hi+1)/2;
					if(v[mid]+w<=v[i]){
						lo=mid;
					}
					else{
						hi=mid-1;
					}
				}
				dp[i][j]=min(dp[i][j], dp[lo][j-1]);
			}
			if(v[0]+2*w>v[i]){
				dp[i][j]=min(dp[i][j], ll(1));
			}
			else{
				ll lo=0, hi=i-1;
				while(lo<hi){
					ll mid=(lo+hi+1)/2;
					if(v[mid]+2*w<=v[i]){
						lo=mid;
					}
					else{
						hi=mid-1;
					}
				}
				dp[i][j]=min(dp[i][j], dp[lo][j]+1);
			}
		}
	}
	if(dp[n-1][p]<=q){
		return true;
	}
	return false;
}
void solve(){
	ll n, p, q;
	cin>>n>>p>>q;
	vector<ll> v(n);
	rep(i, 0, n){
		cin>>v[i];
	}
	sort(v.be, v.en);
	if(p+q>=n){
		cout<<1;
	}
	else{
		ll lo=1, hi=v[n-1];
		while(lo<hi){
			ll mid=(lo+hi)/2;
			bool f=check(n, p, q, mid, v);
			if(f) hi=mid;
			else lo=mid+1;
		}
		cout<<hi;
	}
}
int main(){
	ios_base::sync_with_stdio();
	cin.tie(0);
	ll t=1;
	//~ cin>>t;
	while(t--){
		solve();
	}
	return 0;
}

Subtask #1

50.0 / 50.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	16 ms	31728 KB	Output is correct
2	Correct	16 ms	31644 KB	Output is correct
3	Correct	15 ms	31692 KB	Output is correct
4	Correct	15 ms	31720 KB	Output is correct
5	Correct	15 ms	31684 KB	Output is correct
6	Correct	15 ms	31700 KB	Output is correct
7	Correct	17 ms	31724 KB	Output is correct
8	Correct	15 ms	31700 KB	Output is correct
9	Correct	16 ms	31732 KB	Output is correct
10	Correct	15 ms	31700 KB	Output is correct
11	Correct	18 ms	31744 KB	Output is correct
12	Correct	16 ms	31700 KB	Output is correct
13	Correct	15 ms	31672 KB	Output is correct
14	Correct	14 ms	31700 KB	Output is correct
15	Correct	15 ms	31696 KB	Output is correct

Subtask #2

0 / 50.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	21 ms	31700 KB	Output is correct
2	Correct	15 ms	31644 KB	Output is correct
3	Correct	17 ms	31768 KB	Output is correct
4	Correct	16 ms	31736 KB	Output is correct
5	Correct	15 ms	31724 KB	Output is correct
6	Correct	16 ms	31648 KB	Output is correct
7	Correct	41 ms	31656 KB	Output is correct
8	Correct	157 ms	31752 KB	Output is correct
9	Correct	847 ms	31700 KB	Output is correct
10	Execution timed out	1081 ms	31700 KB	Time limit exceeded
11	Halted	0 ms	0 KB	-